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For 1990-2009 cars only

Engine Control Module Scan Tool Information 2.0L Diesel

Table 1: Engine Control Module Scan Tool Data
Table 2: Engine Control Module (ECM) Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. This is a master list arranged in alphabetical order and not all the parameters listed are in every engine platform.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis.

Engine Control Module Scan Tool Data

Parameter

System State

Expected Value

Description

Base Operating Conditions: Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop

5 Volt Reference 1, Reference 2, or Reference 3

Ignition ON

OK

This parameter displays the output voltage from the 5-volt reference circuit to the control module.

A/C Disengage Reason

A/C OFF

Invalid

This parameter displays the A/C compressor disengage reason. There are 8 different possible faults for the A/C compressor to disengage.

A/C High Side Pressure Sensor

A/C OFF

0-5 Volts

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

0-5 Volts

A/C High Side Pressure Sensor

A/C OFF

700-900 kPa (101-130 psi)

This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

900-1300 kPa (130-174 psi)

A/C Compressor Clutch Relay Command

A/C ON

On

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal

A/C ON

Yes

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

Accelerator Pedal Position Sensors

--

0%

This parameter displays the angle of accelerator pedal position as calculated by the control module using the signals from the APP sensors.

Alternator L Terminal

--

ON

This parameter displays whether the control module is allowing the generator to operate.

Ambient Air Temperature Calculated

--

Varies

This parameter displays the calculated ambient air temperature.

APP at Idle

--

Yes

This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module using the signals from the APP sensors.

APP Sensor 1 or 2

--

APP 1-1.02 Volts

APP 2-0.51 Volts

This parameter displays the voltage of each APP sensor signal circuit as measured by the control module.

APP Sensor 1 or 2 Position

--

APP 1-0%

APP 2-0%

This parameter displays the percent of each APP sensor signal circuit as measured by the control module.

Aux Htr. Relay 1 Command

--

OFF

This parameter displays the commanded state of the aux heater relay 1 control circuit.

Aux Htr. Relay 2 and 3 Command

--

OFF

This parameter displays the commanded state of the aux heater relay 2 and 3 control circuit.

Aux Heater Request

--

OFF

This parameter displays the requested state of the aux heater.

BARO

--

65-104 kPa (8-16 psi) - Varies with altitude

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

BARO

--

0-5 Volts - Varies with altitude

This parameter displays the barometric pressure in voltage. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Battery Voltage

Ignition ON

B+

This parameter displays the voltage measured at the battery circuit of the control module.

Boost Pressure Sensor

--

82-110 kPa (12-16 psi)

This parameter displays the turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.

Boost Pressure Sensor

--

1.45-1.75 Volts

This parameter displays the voltage of the turbocharger boost pressure inside the engine calculated by the control module based on the signal from the Boost pressure sensor.

Brake Lamps Brake Pedal Switch Signal

--

Released

This parameter displays the state of the brake pedal as determined by the stop lamp pedal switch.

Calculated Air Flow

--

630-690 g/s

This parameter displays the calculated air flow into the engine. The calculation is used in several diagnostics to determine when to run the diagnostics.

Calculated DPF Flow

--

24600-27000 Liters/Hours

The parameter displays the calculated flow of DPF.

Clutch Pedal Switch

--

Applied

This parameter displays the current state of the clutch pedal as determined by the control module. The control module monitors the pedal switch on the clutch pedal for vehicles equipped with a manual transmission.

Cruise Control

Cruise Control ON

Yes

This parameter displays the status of the cruise control system as determined by the control module.

Cruise Control Disengage 1-6 History

--

Reason

This parameter displays the history of the action taking with the cruise system.

Cruise Control ON/OFF Switch

Cruise Control ON

Yes

This parameter displays the state of the cruise ON/OFF switch input to the control module.

Cruise Control Release Brake Pedal Switch

--

Released

This parameter displays the state of the brake pedal as determined by the control module. The control module monitors the pedal switch on the brake pedal for vehicles equipped with an automatic transmission. The control module uses this information to release the torque convertor clutch when the brake pedal is applied.

Cruise Resume/Accelerator Switch

Cruise Resume/Accel. Switch ON

On

This parameter displays the state of the cruise Resume/Accel switch input to the control module from the cruise control system.

Cruise Control Set/Coast Switch

Cruise Set/Coast Switch ON

On

This parameter displays the state of the cruise Set/Coast switch input to the control module from the cruise control system.

Cooling Fan Control 1, Control 2, or Control 3 Command

Fans Commanded ON

On

This parameter displays the control module commanded state of the fan relay control circuits.

Cylinder Air

--

240.00-280.00 mg/stk

This parameter displays the actual amount of cylinder air.

Desired Boost Pressure

--

98 kPa

This parameter displays the desired turbocharger boost pressure inside the engine as calculated by the control module based on the signal from the Boost pressure sensor.

Desired Cylinder Air

--

240.00-280.00 mg/stk

This parameter displays the difference between the actual amount of cylinder air and the desired amount of cylinder air.

Desired Fuel Rail Pressure

--

42500.0-44500.0 kPa

6215.0-6265.0 psi

This parameter displays the desired fuel rail pressure as calculated by the control module. This value is calculated based on engine speed, engine load, and sensor inputs.

Desired Idle Speed

--

700-800 RPM

This parameter displays the desired engine idle speed as commanded by the control module.

Distance Since DPF Indicator ON without Regeneration

--

Varies

This parameter displays the mileage that has elapsed since the diesel particulate filter indicator was illuminated without a regeneration occurrence.

Distance Since Last DPF Regeneration

--

Varies

This parameter displays the mileage that has elapsed since the last diesel particulate filter regeneration has occurred.

DPF Differential Pressure Particulate Filter Pressure Variance

--

Varies

This parameter displays the percent calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.

DPF Differential Pressure Particulate Filter Pressure Variance

--

0.40-0.60 Volts

This parameter displays the voltage calculated by the control module, based on the input from the exhaust gas temperature sensors when the particulate filter is full and needs a particulate filter regeneration.

DPF Indicator Command

--

OFF

This parameter displays the commanded state of the dpf indicator lamp control circuit.

DPF Regen Command

--

0 Counts

The parameter displays the DPF regeneration command.

DPF Regen Flow Resistance

--

0.000 pa/m³/h

0.000 psi/cfm

This parameter displays the difference between the front and rear pressures at the DPF as calculated by the ECM.

DPF Regeneration Inhibit

--

No

The parameter displays if the DPF regeneration was inhibited.

DPF Regeneration Interrupted

--

No

The parameter displays if the DPF regeneration was interrupted.

DPF Soot Mass

--

2g-8g

This parameter displays the amount of calculated soot in exhaust particulate filter.

    

Cylinders 1-4 Pilot Injection Command

--

360-380 microseconds

This parameter displays the commanded on time of the fuel injectors for the pilot injection pulse. The scan tool will display a higher value for a longer injection pulse.

ECM Authentication Status

Ignition ON

Valid

This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.

ECM Challenge Status

Ignition ON

Invalid

This parameter displays the status of the control module this ignition cycle. The scan tool will display valid when an internal control module reset has occurred this ignition cycle. The scan tool will display invalid when no internal control module reset has occurred this ignition cycle.

ECM Response Source

Ignition ON

Normal

This parameter displays the status of the control module response this ignition cycle.

ECT Sensor

--

-39 to +140°C ( -38 to +284°F)

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

ECT Sensor

--

0-5 Volts

This parameter displays the voltage calculated by the control module from the engine coolant temperature (ECT) sensor.

EGR Position Command

--

40-55%

This parameter displays the percent of the duty cycle commanded by the control module.

EGR Solenoid Valve Command

--

40-55%

This parameter displays the percent of the EGR solenoid commanded by the control module.

EGR Solenoid Valve Command

--

OFF

This parameter displays the state of the control circuit for EGR solenoid as commanded by the control module.

Engine Load

Engine Idling

20-35%

This parameter displays the percent of the calculated engine load based on inputs to the control module from various engine sensors.

Engine speed at 2,500 RPM

15-25%

Engine Oil Level Switch

--

OK

This parameter displays the status of the engine oil level switch as determined by the control module. The control module uses this information to turn on the low engine oil lamp if the engine oil level remains approximately 1 quart low for a sufficient amount of time.

Engine Oil Pressure Switch

--

OK

This parameter displays the pressure of the engine oil calculated by the control module using a signal from the engine oil pressure (EOP) sensor.

Engine Run Time

Engine Operating

0:00:00

Increments when the engine is operating

This parameter displays the time elapsed since the engine was started.

Engine Speed

Engine Cranking

Greater than 60 RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.

Engine Idling

Approximately 750-850 RPM

Exhaust Gas Temperature Sensor 1 or 2

--

EGT 1 - +110°C to +140°C ( +230°F to +284°F)

EGT 2 - +80°C to +120°C ( +176°F to +248°F)

This parameter displays the temperature of the exhaust gas calculated by the control module based on the input from the exhaust gas temperature sensors.

Exhaust Gas Temperature Sensor 1 or 2

--

EGT 1 - 1.00-1.15 Volts

EGT 2 - 0.90-1.10 Volts

This parameter displays the voltage calculated by the control module based on the input from the exhaust gas temperature sensors.

Fuel Filter Heater Command

--

OFF

This parameter displays the control module commanded state of the fuel heater control circuit.

Fuel Level Sensor

--

0-100%

This parameter displays the percent of fuel in the fuel tank calculated by the control module.

Fuel Level Sensor Left Tank or Fuel Level Sensor Right Tank

--

0-5 Volts

This parameter displays the voltage received by the control module from the sensor used to monitor the fuel level inside the fuel tanks.

Fuel Pressure Regulator 1

--

1300-1400 mA

This parameter displays the control modules commanded state of the fuel rail pressure regulator 1.

Fuel Pressure Regulator 2

--

500-600 mA

This parameter displays the control modules commanded state of the fuel rail pressure regulator 2.

Fuel Pressure Regulator 2 Control Circuit Command

--

20%

This parameter displays the percent of the fuel rail pressure regulator duty cycle commanded by the control module.

Fuel Pump Command

--

34%

This parameter displays the percent of the control modules commanded state of the fuel pump.

Fuel Pump Relay Command

Ignition ON, engine OFF

Fuel pump on for 2 seconds

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Engine idling

On

Fuel Rail Pressure Sensor

--

42800-43800 kPa

(6207-6352 psi)

This parameter displays the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.

Fuel Rail Pressure Sensor

--

1.40-1.50 Volts

This parameter displays the voltage of the fuel rail pressure calculated by the control module using the signal from the fuel rail pressure (FRP) sensor.

Fuel Temperature Sensor

--

25 to 40°C (77 to 104°F)

This parameter displays the fuel temperature calculated by the control module based on input from the fuel temperature sensor.

Fuel Temperature Sensor

--

2.80 Volts

This parameter displays the voltage calculated by the control module based on input from the fuel temperature sensor.

Generator F Terminal Signal

--

25-35%

This parameter displays the commanded state of the generator by the control module.

Glow Plug

--

0%

This parameter displays the percent of the voltage supply to the glow plugs as measured by the control module.

Glow Plug Command

--

OFF

This parameter displays the control module commanded state of the glow plug.

Glow Plug Lamp Command

--

OFF

This parameter displays the commanded state of the glow plug lamp circuit by the control module.

IA Flow Valve Motor Command

--

55-65%

This parameter displays the percent of the control modules commanded state of the intake air flow valve.

IAT Sensor 1 or Sensor 2

--

-39 to +140°C (-38 to +284°F)

This parameter displays the temperature of the air entering the engine air duct calculated by the control module based on the input from the intake air temperature sensors.

Ignition 0 Signal

Ignition ON

Active

This parameter displays the voltage measured at the ignition 0 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 0 position.

Ignition 1 Signal

Ignition ON

Active

This parameter displays the voltage measured at the ignition 1 circuit of the control module. Voltage is applied to the control module when the ignition switch is in the ignition 1 position.

Immobilizer Auto Learn Counter

--

0 Counts

This parameter displays the status of the theft deterrent system password learn.

Immobilizer Password Learn Enabled

Ignition ON

No

This parameter indicates the status of the theft deterrent system password learn.

Immobilizer Password Programmed

--

Yes

This parameter indicates the status of the immobilizer system. The scan tool will display YES if the immobilizer system is ready to be programmed.

Immobilizer Security Code Accepted

Ignition ON

No

This parameter indicates the status of the theft deterrent system security code.

Immobilizer Security Code Lockout

Ignition ON

Active

This parameter Indicates if the theft deterrent system is disabling fuel delivery.

Immobilizer Security Code Programmed

--

No

This parameter indicates the status of the security system.

Immobilizer System State

--

Release

This parameter indicates the status of the immobilizer system.

MAF Sensor

--

On

This parameter indicates the quantity calculated by the control module based on a signal from the mass air flow (MAF) Sensor.

Main Injection Fuel Rate

--

6.5 mm³

This parameter displays the air to fuel ratio based on the oxygen sensor inputs. The ECM uses the fuel trims to adjust fueling in order to attempt to maintain a certain air fuel ratio.

Main Injection Timing

--

On

This parameter displays the current timing of the main injection pulse as calculated by the control module.

MAP Sensor

--

95-104 kPa

This parameter indicates the manifold absolute pressure inside the engine as calculated by the control module based on the signal from the manifold absolute pressure (MAP) sensor.

MIL Command (MIL)

--

Off

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

Pilot Injection Trim Average

--

10-36 microseconds

This parameter displays the average commanded on time of the fuel injectors for the pilot injection pulse.

Park/Nuetral Position Switch

--

Park/Neutral

This parameter displays whether the transmission range selector is in park/neutral or in gear.

Starter Relay Command

--

Off

This parameter displays the commanded state of the starter relay.

Turbocharger Vane Position Solenoid Valve Command

TCC Enable Solenoid Command ON

80%

This parameter displays the percent of the vane position control solenoid from the control module.

Throttle Position Sensor

--

55-70%

This parameter displays the percent of throttle opening as calculated by the control module using information from the TP sensor.

Vehicle Speed Sensor

--

0 Km/h

0 mph

This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).

Water In Fuel Sensor

--

Off

This parameter displays the commanded state of the water in fuel lamp by the control module.

Engine Control Module (ECM) Scan Tool Output Controls

Output Control

Description

A/C Compressor Clutch Relay

Note: The A/C Relay Command parameter may not change states when using this output control.

This function activates the A/C compressor relay. The normal commanded state of the A/C relay is OFF. The A/C compressor will turn ON/OFF when commanded ON/OFF. The system remains in the commanded state for approximately 5 seconds. The engine control module (ECM) will inhibit the operation of the A/C relay when the ambient air temperature is low.

Alternator Lamp

This function activates the alternator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.

Aux Heater Relay 1

Note: This function is only allowed with the ignition ON, engine OFF.

This function controls the aux heater relay 1.

Aux Heater Relay 2 & 3

Note: This function is only allowed with the ignition ON, engine OFF.

This function controls the aux heater relays 2 and 3.

Cooling Fan Relay 1

This function controls the low speed cooling fan relay. When commanded ON, the cooling fan will turn ON at low speed for approximately 5 seconds.

Cooling Fan Relays 2 & 3

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.

Cooling Fan Relays 1, 2 & 3

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed.

Cranking Speed Test

Note: This function is only allowed with the ignition ON, engine OFF.

This function enables the ECM to detect engine speed of each cylinder without activating the fuel injectors.

Cruise Lamp

This function activates the cruise control lamp. The cruise control indicator lamp will remain illuminated until cancelled by the scan tool.

Desired Idle Speed Adjustment

Note: This function is only allowed with the engine idling.

This function adjusts the engine speed in 25, 100, or 500 RPM increments between 600-1500 RPM. The Device Control will not change unless changed or cancelled by the scan tool.

DPF Indicator

This function activates the DPF lamp. The DPF indicator lamp will remain illuminated until cancelled by the scan tool.

DPF Reset Replace DPF

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the DPF has been replaced.

DPF Reset Replace ECM

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the ECM has been replaced.

DPF Reset Replace Injectors

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after one or more injectors have been replaced.

DPF Reset Replace Pressure Sensor

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values for the diesel particulate filter in the ECM after the DPF pressure sensor has been replaced.

EGR Solenoid Valve

This function opens or closes the exhaust gas recirculation (EGR) solenoid. The EGR solenoid increases or decreases in 10 percent increments. The device control will not change unless changed or cancelled by the scan tool.

Engine High Temp. Lamp

This function activates the engine high temperature lamp. The engine high temperature lamp will remain illuminated until cancelled by the scan tool.

Engine Oil Life Reset

This function turns OFF the change oil lamp and resets the values in the ECM.

Fuel Filter Heater

This function activates the fuel heater relay ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.

Fuel Pump Enable

Note: This function is only allowed with the ignition ON, engine OFF.

This function activates the fuel transfer pump or prime pump (depending on application) ON or OFF. The Device Control will not change unless changed or cancelled by the scan tool.

Fuel Quantity Test

Note: This function is only allowed with the engine idling.

This function enables the engine control module (ECM) to detect the fuel quantity in each cylinder.

Fuel Trim Reset

This function resets the fuel trim data in all fuel trim cells.

Generator L-Terminal

Note: This function is only allowed with the engine idling.

This function controls the system voltage. When commanded ON, normal system voltage output is present. When commanded OFF, system voltage output is no longer present, Ignition 1 signal continues to drop, Gen L-Terminal goes to OFF and Gen F-Terminal continues to drop.

Glow Plugs

This function activates the Glow Plug Controller ON or OFF. The Device Control will be aborted after 12 seconds for the first activation, and after 5 seconds for every other activation. The Device Control is inhibited if the engine is running.

Glow Plug Lamp

This function activates the glow plug indicator lamp. The glow plug indicator lamp will remain illuminated until cancelled by the scan tool.

Idle Speed Control

Note: This function is only allowed with the engine idling.

This function adjusts the engine speed in 25, 100, or 500 RPM increments between 600-1500 RPM. The Device Control will not change unless changed or cancelled by the scan tool.

Idle Speed Test

Note: This function is only allowed with the engine idling.

This function enables the ECM to detect engine speed of each cylinder without making any fuel correction.

Malfunction Indicator Lamp (MIL)

This function activates the malfunction indicator lamp (MIL). The MIL will remain illuminated until cancelled by the scan tool.

Reset Injection Value - All Cyl.

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after all the fuel injectors have been replaced.

Reset Injection Value - Cyl. 1

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 1 fuel injector has been replaced.

Reset Injection Value - Cyl. 2

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 2 fuel injector has been replaced.

Reset Injection Value - Cyl. 3

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 3 fuel injector has been replaced.

Reset Injection Value - Cyl. 4

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned values in the ECM after cylinder 4 fuel injector has been replaced.

Reset Injection Value - ECM

Note: This function is only allowed with the ignition ON, engine OFF.

This function resets the learned fuel injector values in the ECM after the ECM has been replaced.

Throttle Blade Control

Note: This function is only allowed with the ignition ON, engine OFF.

This function opens or closes the throttle blade. The throttle blade increases or decreases in 10 percent increments. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).
    • The ignition is ON, with the engine OFF.
    • The ECM is not commanding a throttle learn.

The system remains in the commanded state until cancelled by the scan tool.

Turbocharger Vane Position Solenoid Vlave

Note: This function is only allowed with the engine idling.

Cycles the turbocharger vane position solenoid to 95 percent boost and back to 0 percent boost. The device control is limited to engine speeds less than 2,000 RPM.

Engine Control Module Scan Tool Information 1.8L, 2.0L

Table 1: Engine Control Module Scan Tool Data
Table 2: Engine Control Module (ECM) Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. This is a master list arranged in alphabetical order and not all the parameters listed are in every engine platform.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis.

Engine Control Module Scan Tool Data

Parameter

System State

Expected Value

Description

Base Operating Conditions: Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop

5 Volt Reference 1or 2

Ignition ON

5 Volts

This parameter displays the output voltage from the 5-volt reference circuit to the control module. This parameter only supports one 5-volt reference output from the control module.

A/C High Side Pressure

A/C OFF

0-5 Volts

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

0-5 Volts

A/C High Side Pressure

A/C OFF

450-650 kPa (65-95 psi)

This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

650-800 kPa (95-105 psi)

A/C Relay Command

A/C ON

On

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal

A/C ON

Yes

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

Air Flow Calculated

--

3-6 g/s

This parameter displays the calculated air flow into the engine that is based on manifold absolute pressure. The calculation is used in several diagnostics to determine when to run the diagnostics.

Air Fuel Ratio

--

Ratio 14.7:1

This parameter displays the air to fuel ratio based on the oxygen sensor inputs. The engine control module (ECM) uses the fuel trims to adjust fueling in order to attempt to maintain an air fuel ratio of 14.7:1.

APP Indicated Angle

--

Varies

This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module using the signals from the APP sensors.

APP Sensor 1or 2

--

Varies

This parameter displays the actual percentage of each APP sensor signal circuit as measured by the control module.

BARO

--

65-104 kPa (8-16 psi) - Varies with altitude

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Case Diagnostic Learning

--

Learned

This parameter displays Learned if the control module has completed the CKP System Variation Learn Procedure.

Catalytic Converter Protection Active

--

No

This parameter displays if the control module is commanding catalytic converter protection.

Cmmd. A/F Equivalence Ratio

--

Ratio 1.0:1

This parameter displays the air to fuel ratio based on throttle state. The control module changes the ratio for acceleration or deceleration.

CMP Active Counter

--

1-3 Counts

This parameter displays the camshaft position (CMP) active counts. If the control module does not detect a signal from the CMP sensor, the counter will not increment.

Coolant Hot Lamp

--

Off

This parameter displays the control modules commanded state of the hot mode lamp.

Cruise Control Active

Cruise Control ON

Yes

This parameter displays the status of the cruise control system as determined by the control module.

Cruise Disengage 1-5 History

--

Varies

This parameter displays the history of the action taking with the cruise system.

Cruise Lamp Command

Cruise Control ON

Yes

This parameter displays the state of the cruise lamp to the instrument panel (IP) cluster as requested by the control module.

Cruise ON/OFF Switch

Cruise Control ON

Yes

This parameter displays the state of the ON/OFF switch input to the control module.

Cruise Resume/Accel. Switch

Cruise Resume/Accel. Switch ON

Active

This parameter displays the state of the Resume/Accel switch input to the control module from the cruise control system.

Cruise Set/Coast Switch

Cruise Set/Coast Switch ON

Active

This parameter displays the state of the Set/Coast switch input to the control module from the cruise control system.

Decel Fuel Cut Off

--

Inactive

This parameter displays the status of the operating mode of the control module used to turn off the fuel injectors during certain deceleration conditions.

Desired EGR Position

--

Varies

This parameter displays the desired exhaust gas recirculation (EGR) position as commanded by the control module.

Desired IAC Position

--

Counts

This parameter displays the desired idle air control (IAC) position as commanded by the control module.

Desired Idle Speed

--

750-950 RPM

This parameter displays the desired engine idle speed as commanded by the control module.

Distance Since DTC Cleared

--

Varies

This parameter displays the mileage that has elapsed since the DTC cleared.

ECT Sensor

--

-39 to +140°C ( -38 to +284°F)

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

EGR Flow Test Count

--

Counts

This parameter displays the number of EGR flow test samples collected during the current ignition cycle.

EGR Learned Minimum Position

--

Varies

This parameter displays the exhaust gas recirculation (EGR) valve minimum position in percent of range learned by the control module.

EGR Learned Minimum

--

Varies

This parameter displays the learned minimum value of the EGR valve as recorded by the control module during the last learn procedure.

EGR Position Sensor

--

Varies

This parameter displays the actual EGR pintle position in percentage.

EGR Position Sensor

--

Varies

This parameter displays the actual EGR pintle position in volts.

EGR Position Variance

--

Counts

This parameter displays the difference between the actual command of the EGR valve and the desired position of the EGR valve. This parameter displays the state of the EVAP vent solenoid as commanded by the control module.

EGR Solenoid Command

--

Varies

This parameter displays the state of the control circuit for EGR solenoid as commanded by the control module.

Engine Load

Engine Idling

25-40%

This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.

Engine speed at 2,500 RPM

25-40%

Engine Run Time

Engine Operating

0:00:00

Increments when the engine is operating

This parameter displays the time elapsed since the engine was started.

Engine Speed

Engine Cranking

Greater than 60 RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.

Engine Idling

Approximately 750-950 RPM

EVAP Purge Solenoid Command

--

0-100%

This parameter displays the on-time or duty cycle of the EVAP canister purge solenoid commanded by the control module. Zero percent indicates no purge. One hundred percent indicates full purge.

EVAP Vent Solenoid Command

--

Venting

This parameter displays the state of the EVAP vent solenoid as commanded by the control module.

Fail Counter

--

Counts

This parameter displays the number of times a DTC failed

Fan High Speed Command

Fan High Speed ON

On

This parameter displays the control module commanded state of the fan relay control circuit.

Fan Low Speed Command

Fan Low Speed ON

On

This parameter displays the control module commanded state of the fan relay control circuit.

Fuel Level Gage Command

--

Varies

This parameter displays the control module commanded state of the fuel gage control circuit.

Fuel Level to Cluster

--

Varies

This parameter displays the control module commanded state of the fuel gage control circuit.

Fuel Level Sensor

--

0-100%

This parameter displays the amount of fuel in the fuel tank in percent of range, as calculated by the control module.

Fuel Level Sensor

--

0-5 Volts

This parameter displays the voltage signal received by the control module from the fuel level sensor.

Fuel Pump Relay Command

Ignition ON, engine OFF

Fuel pump on for 2 seconds

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Engine idling

On

Fuel Tank Pressure Sensor

--

Varies

This parameter displays the pressure/vacuum inside the fuel tank. A negative value indicates a vacuum, while a positive value indicates a pressure.

Fuel Tank Pressure Sensor

--

0-5 Volts

This parameter displays the voltage signal received by the control module from the fuel tank pressure (FTP) sensor.

Fuel Trim Cell

--

Cell Number

This parameter displays what fuel trim cell that is currently active.

Fuel Trim Learned

--

Enabled

This parameter displays Enabled when conditions are appropriate for enabling long term fuel trim corrections. This indicates that the long term fuel trim is adapting continuing amounts of short term fuel trim. If the scan tool displays Disabled, then long term fuel trim will not respond to changes in short term fuel trim.

HO2S 1 or HO2S 2 Heater

--

Varies

This parameter displays the amperage of the HO2S heater commanded by the control module.

IAC Position

--

15-40 counts

 

IAT Sensor

--

-39° to +140°C

(-38° to +284°F)

This parameter displays the temperature of the air entering the air induction system based on input to the control module from the intake air temperature (IAT) sensor.

Ignition 1 Signal

--

B+

This parameter displays B+ when the control module detects a voltage at the ignition 1 input terminal.

IMT Valve Command

--

Off

This parameter displays the commanded state of the IMT valve solenoid by the control module.

IMT Valve Position Sensor

--

Varies

This parameter displays the percentage in range based on input to the control module the control module from the IMT valve position sensor.

Injector PWM Average

--

0-9 ms

This parameter displays the average pulse width of the fuel injectors as determined by the control module.

Knock Retard

--

Degrees

This parameter indicates the amount of spark advance the control module removes from the ignition control (IC) spark advance in response to the signal from the knock sensors.

KS Active Counter

--

Counts

This parameters displays the number of times the control module detects activity from the knock sensor.

Long Term FT

--

0-2%

This parameter displays the commanded Long Term Fuel Trim correction by the control module.

Long Term FT Average

--

0%

This parameter displays the commanded Long Term Fuel Trim correction by the control module.

Loop Status

--

Closed Loop

This parameter displays the state of the fuel control system as commanded by the control module. Closed Loop operation indicates that the control module is controlling the fuel delivery based off the oxygen sensors input signal. In Open Loop operation the control module ignores the oxygen sensor input signal and bases the amount of fuel to be delivered on other sensor inputs.

Low Fuel Lamp Command

Low Fuel Lamp Command ON

On

This parameter displays the control modules commanded state of the low fuel lamp.

MAP Sensor

--

32-50 kPa

This parameter displays the pressure from the MAP sensor to the control module

MAP Sensor

--

0-5 Volts

This parameter displays the signal voltage from the MAP sensor to the control module.

MIL Command

MIL Command ON

On

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

Mileage Since First Failure

--

Varies

This parameter displays the mileage that has elapsed since the first emission failure.

Mileage Since Last Failure

--

Varies

This parameter displays the mileage that has elapsed since the last emission failure.

Misfire Current Cyl. 1-4

--

0-255 Counts

This parameter displays the number of misfires that have been detected during the last 200 cylinder firing events. The counters may normally display some activity, but the activity should be nearly equal for all of the cylinders, and in low numbers.

Misfire Detects Rough Road

Rough Road Detected

Yes

This parameter displays the detection of a rough road during misfire detection by the control module.

Misfire History Cyl. 1-4

--

0-255 Counts

The misfire history counters display the total level of misfire that has been detected on each cylinder. The misfire history counters will not update or show any activity until a misfire DTC P0300 has become active. The misfire history counters will update every 200 cylinder firing events.

Not Run Counter

--

Counts

This parameter displays the number of times a DTC does not run.

O2S/HO2S 1 or 2

--

Varies 400-800 mV

This parameter displays the voltage output from the H/O2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

O2S/HO2S 1 Ready

--

Yes

This parameter displays that the HO2S 1 is at operating temperature.

Pass Counter

--

Counts

This parameter displays the number of times a DTC passed.

PNP Switch

--

Park/Neutral

This parameter displays whether the transmission range selector is in park/neutral or in gear.

Power Enrichment

--

Inactive

This parameter displays the status of the operating mode of the control module used to increase fuel delivery during certain acceleration conditions.

Power Steering Pressure Switch

--

Normal Pressure

This parameter displays the state of the power steering pressure switch.

Rich/Lean to Lean/Rich Ratio Sensor 1

--

Counts

This parameter displays the oxygen sensor rich/lean to lean/rich ratio. The rich/lean average is divided by the lean/rich average in order to determine the oxygen sensor ratio.

Rich/Lean to Transition Sensor 1

--

Counts

This parameter displays the oxygen sensor rich/lean and lean/rich switches. A switch is when the oxygen sensor voltage goes above 450 mV and below 450 mV.

Reduced Engine Power

--

No

This parameter displays the status of the operating mode of the control module used to reduce engine power to prevent catalytic converter or engine damage or due to a Throttle Actuator Control (TAC) system failure.

Rough Road Sensor

--

0-5 Volts

This parameter displays the voltage from the rough road sensor.

Rough Road Signal-ABS

--

0-5 Volts

This parameter displays the voltage from the ABS module for the rough road signal.

Short Term FT Avg.

--

-3% to +3%

This parameter displays the short-term correction to the fuel delivery by the control module in response to oxygen sensor. If the oxygen sensor indicates a lean air/fuel mixture, the control module will add fuel increasing the short term fuel trim above 0. If the oxygen sensor indicates a rich air/fuel mixture, the control module will reduce fuel decreasing the short term fuel trim below 0.

Short Term FT

--

-3% to +3%

This parameter displays the short-term correction to the fuel delivery by the control module in response to oxygen sensor. If the oxygen sensor indicates a lean air/fuel mixture, the control module will add fuel increasing the short term fuel trim above 0. If the oxygen sensor indicates a rich air/fuel mixture, the control module will reduce fuel decreasing the short term fuel trim below 0.

Spark

--

-20 to +40Degrees

This parameter displays the amount of spark advance the control module is commanding on the ignition control circuits. The control module determines the desired advance.

Start Up ECT

--

-39° to +140°C

(-38° to +284°F)

This parameter displays the temperature of the engine coolant on start up based on input to the control module from the ECT sensor.

Start Up IAT

--

-39° to +140°C

(-38° to +284°F)

This parameter displays the temperature of the intake air at start in the air induction system based on input to the control module from the IAT sensor.

SVS Lamp Command

SVS Lamp Command ON

On

This parameter displays the control modules commanded state of the service vehicle soon lamp.

TAC Motor Command

TAC Motor Command ON

Varies

This parameter displays the percentage of the commanded state of the TAC motor by the control module.

TCC Enable Solenoid Command

TCC Enable Solenoid Command ON

On

This parameter displays the control module commanded state of the TCC solenoid.

Throttle Plate at Idle

--

Yes

This parameter displays whether the throttle plate at idle or not as calculated by the control module using information from the throttle position (TP) sensor. The scan tool will display Yes for the throttle plate to be at idle. The scan tool will display No when the throttle plate is opened.

Total Misfire

--

Counts

This parameter displays the total number of cylinder firing events that the control module detected as misfires for the last 200 crankshaft revolution sample period.

TP Angle

--

Varies

This parameter displays the percent of throttle opening as calculated by the control module using information from the two TP sensors.

TP Desired Angle

--

Varies

This parameter displays the desired TP angle commanded by the control module.

TP Indicated Angle

--

Varies

This parameter displays the actual TP angle indicated by the control module using information from the two TP sensors.

TP Sensor

--

0.0-0.3 Volts

This parameter displays the actual voltage on the TP sensor signal circuit as measured by the control module.

TP Sensor

--

5-15%

This parameter displays the percent of throttle opening as calculated by the control module using information from the throttle position (TP) sensor.

TP Sensor 1 or 2

--

Varies

This parameter displays the percent of throttle opening as calculated by the control module using information from the throttle position (TP) sensor.

Transmission Gear Position Signal

--

Park/Neutral

This parameter displays the position of the transmission gear selector that is transmitted over the serial data circuit from the transmission control module (TCM).

TWC Temperature Calculated

--

Varies

This parameter displays the catalytic converter temperature as calculated by the control module.

Vehicle Security Status

--

Disabled

This parameter displays the status of the vehicle theft deterrent system. The normal parameter display for the theft deterrent system is Disabled. If a condition exists with the theft deterrent system the parameter will display Enabled and the vehicle will not start.

Vehicle Speed Sensor

--

0 Km/h

0 mph

This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).

Warm-ups Since DTC Cleared

--

Counts

This parameter displays the number of warm-ups since the DTC was cleared.

Wheel/Vehicle Speed Input

--

0 Km/h

0 mph

This parameter displays the speed of the vehicle as calculated by the control module from information received from the vehicle speed sensor (VSS) or wheel speed sensor depending on application.

Engine Control Module (ECM) Scan Tool Output Controls

Output Control

Description

A/C Relay

Important: The A/C Relay Command parameter may not change states when using this output control.

This function activates the A/C compressor relay. The normal commanded state of the A/C relay is None. The A/C compressor will turn ON/OFF when commanded ON/OFF. The system remains in the commanded state until cancelled by the scan tool. This output can also be monitored on the scan tool data parameter A/C Relay Command. The engine control module (ECM) will inhibit the operation of the A/C relay when the ambient air temperature is low.

Crankshaft Position Variation Learn

This function enables the engine control module (ECM) to learn the variations in the crankshaft position (CKP) system. The ECM will learn the variations once the following conditions are met:

    • Engine coolant temperature (ECT) is more than a predetermined value.
    • All the instructions on the scan tool have been completed.
    • Hold the accelerator pedal at wide open throttle (WOT) for 5 fuel cut-offs, as specified on the scan tool, then release accelerator pedal.

The ECM learns the variation values on the deceleration from fuel cut-off.

EGR Solenoid

Important: The EGR Position Sensor parameter may not properly change states when using this output control.

This function activates the exhaust gas recirculation (EGR) solenoid that controls EGR valve position. The normal commanded state is None. The system will increase or decrease the amount of EGR opening by 10 percent increments within a range of 0-100 percent. The EGR Position sensor parameter may not change states until commanded to 40 percent. This output can also be monitored on the scan tool data parameter EGR Position Sensor. The system remains in the commanded state until cancelled by the scan tool. If the engine is running, too much EGR will result in a rough idle and/or stalling.

EVAP Purge Solenoid

Important: 

   • This function may be disabled if there is an EVAP DTC set.
   • The EVAP Purge Solenoid Command parameter may not properly change states when using this output control.

This function controls the EVAP purge solenoid valve. The normal commanded state is None. The system will increase or decrease the amount of purge by changing the duty cycle of the purge valve in 10 percent increments within a range of 0-100 percent. The system remains in the commanded state until cancelled by the scan.

EVAP Vent Solenoid

Important: This function may be disabled if there is an EVAP DTC set.

This function controls the EVAP vent solenoid. The normal commanded state is None. When commanded ON, the vent valve switches to Not-venting. When commanded OFF, the vent valve switches to Venting. The system remains in the commanded state unless one of the following conditions occurs:

    • Cancelled by the scan tool
    • The fuel tank pressure (FTP) sensor exceeds a predetermined value.

EVAP Purge/Seal

Simultaneously activates the purge solenoid in 10 percent increments from 0 to 100 percent and the vent solenoid. The device control will be aborted and inhibited if the FTP sensor exceeds 19 mm Hg (10 in H2O).

Fan High Speed

This function operates one engine cooling fan at high speed by enabling the fan high speed relay. The normal commanded state of the relay is None. When commanded ON/OFF, the cooling fan turns ON/OFF. The system remains in the commanded state until cancelled by the scan tool. The ECM allows relay control when the following conditions are met:

    • The ignition is ON, with the engine OFF.
    • The engine is running.
    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than a predetermined value.

Fan Low Speed

This function operates one engine cooling fan at high speed by enabling the fan high speed relay. The normal commanded state of the relay is None. When commanded ON/OFF, the cooling fan turns ON/OFF. The system remains in the commanded state until cancelled by the scan tool. The ECM allows relay control when the following conditions are met:

    • The ignition is ON, with the engine OFF.
    • The engine is running.
    • The transmission must be in Park or Neutral.
    • The A/C request is OFF.
    • The engine coolant temperature is less than a predetermined value.

Fuel Injector Test

Important: DTCs may set when using this output control.

This function operates the selected fuel injector ON/OFF. The normal commanded state is None. The ECM enables or disables the fuel injector ON/OFF when the test is initiated. The fuel injector remains in the commanded state until cancelled by the scan tool. The scan tool initiates the test when the following conditions are met:

    • The engine is running.
    • The vehicle speed is 0 km/h (0 mph).

Fuel Pump Relay

Important: DTCs may set when using this output control.

This function controls the fuel pump relay. The normal commanded state is None. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).

When commanded ON/OFF, the ECM turns the fuel pump relay ON/OFF. If the engine is running and the fuel pump relay is commanded OFF, the engine will stall. This output can also be monitored on the scan tool data parameter Fuel Pump Relay Command. The system remains in the commanded state until cancelled by the scan tool or the ECM detects a vehicle speed.

Engine Speed

This function controls the idle speed override in 25 RPM, 100 RPM, and 500 RPM increments, from the base idle speed to 1,400 RPM. The scan tool initiates the test when the following conditions are met:

    • The transmission is in park or neutral.
    • The engine speed is less than 1,000 RPM.

The engine speed will remain in the commanded state until cancelled by the scan tool.

IAC Motor Position

This function activates the idle air control (IAC) valve to change engine speed. The normal commanded state is None. The system will increase or decrease the amount of IAC opening by 5 percent increments within a range of 500-4,000 RPM. This output can also be monitored on the scan tool data parameter IAC Position. The system remains in the commanded state until cancelled by the tool.

IAC Reset

This function resets the IAC valve position and the learned values for the IAC system in the ECM.

IMT Valve

This function controls the intake manifold tuning (IMT) valve solenoid. The normal commanded state is None. When commanded ON/OFF, the ECM turns the IMT valve solenoid ON/OFF. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).

The system remains in the commanded state until cancelled by the scan tool.

Malfunction Indicator Lamp

Important: The MIL Command parameter may not change states when using this output control.

This function controls the malfunction indicator lamp (MIL). The normal commanded state is None. When commanded ON/OFF, the ECM turns the malfunction indicator lamp (MIL) ON/OFF. This output can also be monitored on the scan tool data parameter MIL Command. The system remains in the commanded state until cancelled by the scan tool.

Throttle Position

This function controls the throttle valve in 10 percent increments. The scan tool initiates the test when the following conditions are met:

    • There are no vehicle speed sensor DTCs set.
    • The vehicle speed is 0 km/h (0 mph).
    • The ignition is ON, with the engine OFF.
    • The ECM is not commanding a throttle learn.

The system remains in the commanded state until cancelled by the scan tool.

Engine Control Module Scan Tool Information 1.4L, 1.6L

Table 1: Engine Control Module Scan Tool Data
Table 2: Engine Control Module (ECM) Scan Tool Output Controls

The Engine Control Module Scan Tool Data List contains all engine-related parameters that are available on the scan tool. This is a master list arranged in alphabetical order and not all the parameters listed are in every engine platform.

Use the Engine Scan Tool Data List only after the following is determined:

    • The Diagnostic System Check - Vehicle is completed.
    • No diagnostic trouble codes (DTCs)
    • On-board diagnostics are functioning properly

The scan tool values from a properly running engine may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents values that would be seen on a normally running engine.

Important: A scan tool that displays faulty data should not be used. The scan tool concern should be reported to the manufacturer. Use of a faulty scan tool can result in misdiagnosis and unnecessary parts replacement.

Only the parameters listed below are referenced in this service manual for use in diagnosis.

Engine Control Module Scan Tool Data

Parameter

System State

Expected Value

Description

Base Operating Conditions: Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop

A/C Evap. Temperature Sensor

--

-40° to +130°C (-40° to +266°°F)

This parameter displays the temperature of the A/C evaporator core based on the input to the control module from the A/C evaporator temperature sensor signal circuit.

A/C High Side Pressure

A/C OFF

0-5 Volts

This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

0-5 Volts

A/C High Side Pressure

A/C OFF

500-2,200 kPa (72-319 psi)

This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

A/C ON

300-1,200 kPa (43-174 psi)

A/C Relay Command

A/C ON

On

This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal

A/C ON

Yes

This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

BARO

--

65-104 kPa (8-16 psi) - Varies with altitude

This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

Case Diagnostic Learning

--

Learned

This parameter displays Learned if the control module has completed the CKP System Variation Learn Procedure.

CASE Learned Cyl. 1-4

--

Counts

This parameter displays the CKP Learn offset in counts between cylinders.

Desired Idle Speed

--

800 RPM

This parameter displays the desired engine idle speed as commanded by the control module.

DTC Set This Ignition

--

No

This parameter displays Yes if a DTC set on the current ignition cycle.

ECT Sensor

--

0-5 Volts

This parameter displays the voltage of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

ECT Sensor

--

-40° to +130°C (-40° to +266°°F)

This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.

EC Ignition Relay Command

Ignition ON

ON

This parameter displays the state of the control circuit for main relay as commanded by the control module.

EGR Position Sensor

--

0.6-0.75 Volts

This parameter displays the actual EGR pintle position in volts.

EGR Solenoid Command

--

0%

This parameter displays the state of the control circuit for EGR solenoid as commanded by the control module.

Engine Load

Engine Idling

20-30%

This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.

Engine speed at 2,500 RPM

10-20%

Engine Speed

Engine Cranking

Greater than 60 RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.

Engine Idling

Approximately 650-900 RPM

EVAP Purge Solenoid Command

--

0-100%

This parameter displays the on-time or duty cycle of the EVAP canister purge solenoid commanded by the control module. Zero percent indicates no purge. One hundred percent indicates full purge.

Fan High

Fan High Commanded ON

ON

This parameter displays the control module commanded state of the fan relay control circuit.

Fan Low

Fan Low Commanded ON

ON/OFF

This parameter displays the control module commanded state of the fan relay control circuit.

Fuel Gage Control

--

0-100%

This parameter displays control module commanded state of the fuel gage control circuit.

Fuel Level

--

0-100%

This parameter displays the amount of fuel in the fuel tank in percent of range, as calculated by the control module.

Fuel Level Sensor

--

0-5 Volts

This parameter displays the voltage signal received by the control module from the fuel level sensor.

Fuel Pump Relay Command

Ignition ON, engine OFF

Fuel pump on for 2 seconds

This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Engine idling

On

HO2S 1 and 2 Heater Command

--

0-100%

This parameter displays the commanded state of the heater control circuit as commanded by the control module.

IAT Sensor

--

-39° to +140°C

(-38° to +284°F)

This parameter displays the temperature of the air entering the air induction system based on input to the control module from the intake air temperature (IAT) sensor.

IAT Sensor

--

0-5 Volts

This parameter displays the IAT sensor voltage.

Idle Switch

--

ON

This parameter displays if the engine is at idle. The parameter will change from ON to OFF when the engine is not at an idle.

Ignition 1 Signal

--

B+

This parameter displays B+ when the control module detects a voltage at the ignition 1 input terminal.

Injector PWM

--

0-9 ms

This parameter displays the average pulse width of the fuel injectors as determined by the control module.

ISC Command

--

0-100%

This parameter displays the ECM command for the idle speed control (ISC) motor position in percentage. The higher the number, the greater the commanded idle speed reads. The ISC responds to changes in the engine load in order to maintain the desired idle speed.

ISC Motor Position Sensor

--

0-100%

This parameter displays the ECM command for the idle speed control (ISC) motor position in percentage. The higher the number, the greater the commanded idle speed reads. The ISC responds to changes in the engine load in order to maintain the desired idle speed.

ISC Motor Position Sensor

--

0-5 Volts

This parameter displays the actual position for the ISC motor position in voltage.

Knock Sensor

--

0-5 Volts

This parameters displays the voltage input to the control module from the knock sensor (KS).

Long Term FT

--

0%

This parameter displays the commanded Long Term Fuel Trim correction by the control module.

Loop Status

--

Closed Loop

This parameter displays the state of the fuel control system as commanded by the control module. Closed Loop operation indicates that the control module is controlling the fuel delivery based off the oxygen sensors input signal. In Open Loop operation the control module ignores the oxygen sensor input signal and bases the amount of fuel to be delivered on other sensor inputs.

LT FT Cruise/Accel.

--

0%

This parameter displays the commanded Long Term Fuel Trim correction by the control module for cruise and acceleration conditions.

LT FT Idle/Decel.

--

0%

This parameter displays the commanded Long Term Fuel Trim correction by the control module for idle and deceleration conditions.

MAP Sensor

--

32-40 kPa

This parameter displays the pressure from the MAP sensor to the control module

MAP Sensor

--

0-5 Volts

This parameter displays the signal voltage from the MAP sensor to the control module.

MIL Command

--

Off

This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.

O2S/HO2S 1 or 2

--

Varies 400-800 mV

This parameter displays the voltage output from the H/O2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

Octane Level

--

Counts

This parameter displays counts.

Short Term FT Avg.

--

-3% to +3%

This parameter displays the short-term correction to the fuel delivery by the control module in response to oxygen sensor. If the oxygen sensor indicates a lean air/fuel mixture, the control module will add fuel increasing the short term fuel trim above 0. If the oxygen sensor indicates a rich air/fuel mixture, the control module will reduce fuel decreasing the short term fuel trim below 0.

Short Term FT

--

-3% to +3%

This parameter displays the short-term correction to the fuel delivery by the control module in response to oxygen sensor. If the oxygen sensor indicates a lean air/fuel mixture, the control module will add fuel increasing the short term fuel trim above 0. If the oxygen sensor indicates a rich air/fuel mixture, the control module will reduce fuel decreasing the short term fuel trim below 0.

Spark

--

2-10 Degrees

This parameter displays the amount of spark advance the control module is commanding on the ignition control circuits. The control module determines the desired advance.

TP Sensor

--

4.0-4.5 Volts

This parameter displays the actual voltage on the TP sensor signal circuit as measured by the control module.

TP Sensor

--

3-5%

This parameter displays the percent of throttle opening as calculated by the control module using information from the throttle position (TP) sensor.

Transmission Gear Position Signal

--

Park/Neutral

This parameter displays the position of the transmission gear selector that is transmitted over the serial data circuit from the transmission control module (TCM).

Vehicle Security Status

--

Disabled

This parameter displays the status of the vehicle theft deterrent system. The normal parameter display for the theft deterrent system is Disabled. If a condition exists with the theft deterrent system the parameter will display Enabled and the vehicle will not start.

Vehicle Speed Sensor

--

Km/h

mph

This parameter displays the speed of the vehicle as calculated by the transmission control module (TCM) from information received from the vehicle speed sensor (VSS).

Engine Control Module (ECM) Scan Tool Output Controls

Output Control

Description

A/C Relay

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the A/C compressor relay. When commanded ON, the A/C compressor will cycle ON/OFF for 3-5 seconds.

EGR Solenoid

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the exhaust gas recirculation (EGR) solenoid. When commanded ON, the EGR solenoid will cycle from 0-100 percent for 3-5 seconds. This output can also be monitored on the scan tool by observing the EGR Position Sensor data parameter.

Engine Controls Ignition Relay

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the engine control ignition relay or MAIN relay. When commanded ON, the engine control ignition relay will cycle ON/OFF for 3-5 seconds.

EVAP Purge Solenoid

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the evaporative emission (EVAP) purge solenoid. When commanded ON, the EVAP purge solenoid will cycle ON/OFF for 3-5 seconds. This output can also be monitored on the scan tool by observing the EVAP Purge Solenoid Command data parameter.

Fan High

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the high speed cooling fan relay. When commanded ON, the cooling fan will turn ON at high speed for 5 seconds.

Fan Low

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the low speed cooling fan relay. When commanded ON, the cooling fan will turn ON at low speed for 5 seconds.

Fuel Pump Relay

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the fuel pump relay. When commanded ON, the fuel pump relay will cycle ON/OFF for 3-5 seconds.

IAC Motor Position

Important: This function is only allowed with the ignition ON, engine OFF.

This function activates the idle air control (IAC) valve to change position. The system will cycle the IAC valve for 3-5 seconds. This output can also be monitored on the scan tool data parameter IAC Position.

Idle Learn Reset

This function resets the base idle value learned by the engine control module (ECM).

ISC Actuator

Important: This function is only allowed with the ignition ON, engine OFF.

This function controls the idle speed control (ISC) actuator. The ECM actuates the ISC actuator for 3-5 seconds when commanded ON. This output can also be monitored on the scan tool by observing the TP Sensor data parameter.

ISC System

This function resets the learned values for the idle speed control (ISC) system in the ECM.

Malfunction Indicator Lamp

This function controls the malfunction indicator lamp (MIL). When commanded ON with the engine running, the ECM turns the (MIL) ON/OFF for 3-5 seconds. When commanded OFF with the ignition ON, engine OFF, the ECM turns the MIL ON/OFF for 3-5 seconds.

Reset ECM

This function resets all the values learned by the ECM.