GM Service Manual Online
For 1990-2009 cars only

Scan Tool Data List Except Holden

The Engine Scan Tool Data List contains all engine related parameters that are available on the scan tool. The list is arranged in alphabetical order. A parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

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

    •  The Diagnostic System Check - Engine Controls is completed.
    •  There are no diagnostic trouble codes (DTCs).
    • The on-board diagnostics are functioning correctly.

Scan tool values from an engine that is operating correctly may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents the values that would be seen on a normal operating engine.

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

Only the parameters listed below are referenced in this service information for use in diagnosis. If all values are within the typical range described below, refer to Symptoms - Engine Controls for diagnosis.

The column labeled Data List indicates where a parameter is located on the scan tool. Review the scan tool operating manual for the exact locations of the data lists. The following is a description of each term listed:

All: The Parameter is in all data lists indicated below.

Eng 1: Engine Data 1

Eng 2: Engine Data 2

Eng 3: Engine Data 3

HO2S: HO2S Data

Scan Tool Parameter

Data List

Parameter Range/Units

Typical Data Values

Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop/Accessories Off

A/C High Side Pressure Sensor

Eng 2

0-5 Volts

Varies

A/C High Side Pressure Sensor

Eng 2, 3

kPa/psi

Varies

A/C Relay Command

Eng 3

On/Off

Off

APP Sensor 1

Eng 2

0-5 Volts

0.6-0.8 Volts

APP Sensor 2

Eng 2

0-5 Volts

0.3-0.5 Volts

BARO

Eng 2

65-104 kPa

Varies with altitude

Cruise Control ON/OFF Switch

Eng 2

ON/OFF

OFF

Cruise Control Set/Coast Switch

Eng 2

ON/OFF

OFF

Cruise Control Resume/Accel Switch

Eng 2

ON/OFF

OFF

Cruise Control

Eng 2

ON/OFF

OFF

Desired Idle Speed

Eng 2

0-8,000 RPM

670 RPM

DTC Set This Ignition

Eng 1

Yes/No

No

ECT Sensor

Eng 1

-40 to +130°C (-40 to +266°F)

Varies

ECT Sensor

Eng 2

0-5 Volts

Varies

EC Ignition Relay Command

Eng 3

On/Off

On

EGR Position Sensor

Eng 2

0-5 Volts

0.6-0.75 Volts

EGR Solenoid Command

Eng 2, 3

0-100%

0%

Engine Load

Eng 1

0-99%

20-30% - Idle

10-20% - 2500 RPM

Engine Run Time

HO2S

HH:MM:SS

Varies

Engine Speed

ALL

0-8,000 RPM

650-750 RPM

EVAP Purge Solenoid Command (If Equipped)

Eng 2, 3

0-100%

Varies

Fan High

Eng 3

On/Off

Varies

Fan Low

Eng 3

On/Off

Varies

Fuel Gage Control

Eng 3

0-100%

Varies

Fuel Level Sensor

Eng 2, 3

0-5 Volts

Varies

Fuel Level Sensor

Eng 2, H02S

0-100%

Varies

Fuel Pump Relay Command

Eng 3

On/Off

On

HO2S Bank 1 and 2 Sensor 1

Eng 1, H02S

0-1,006 mV

Varies 400-800 mV

HO2S Bank 1 and 2 Sensor 2

Eng 1, H02S

0-1,006 mV

Varies 400-800 mV

HO2S Htr. Bn. 1 and 2 Sen. 1 Command

H02S

0-100%

Varies

HO2S Htr. Bn. 1 and 2 Sen. 2 Command

H02S

0-100%

Varies

IAT Sensor

Eng 1

-39 to +140°C (-38 to +284°F)

Varies

IAT Sensor

Eng 2

0-5 Volts

Varies

IMT Valve Command

Eng 3

Open/Closed

Closed

IMT Valve Position Sensor

Eng 3

0-5 Volts

0.9-1.1 Volts

Ignition 1 Signal

Eng 2, 3, HO2S

6-24 Volts

12-15 Volts

Injector PWM Bank 1 and 2 Average

Eng 2

000.0-999.9 ms

2.6-3.8 ms

Knock Sensor

Eng 2

0-5 Volts

Varies

Long Term FT Bank 1 and 2

Eng 1

-50 to +50%

-3 to +3%

Loop Status Bank 1 and 2

Eng 1

Open Loop/Closed Loop

Closed Loop

MAF Sensor

Eng 1

g/s

3.2-4.6 g/s

MAF Sensor

Eng 2

0-5 Volts

0.4-0.8 Volts

MAP Sensor

All

kPa/PSI

32-40 kPa

Varies with Altitude

MAP Sensor

Eng 2

0-5 Volts

1.15-1.3 Volts

MIL Command

Eng 1

On/Off

Off

Short Term FT Average Bank 1 and 2

H02S

-50 to +50%

-3 to +3%

Short Term FT Bank 1 and 2

Eng 1, HO2S

-50 to +50%

-3 to +3%

Spark

Eng 1

-20 to +40 Degrees

2-10 Degrees

TAC Motor Command

Eng 2

0-100%

Varies

TP Indicated Angle

Eng 1

Degrees

6-14%

TP Sensor 1

Eng 2

0-5 Volts

0.5-0.8 Volts

TP Sensor 2

Eng 2

0-5 Volts

4.2-4.5 Volts

Transmission Gear Selector Signal

Eng 3, H02S

Park/Neutral/In Gear

Park/Neutral

Vehicle Security Status (If Equipped)

Eng 3

Enabled/Disabled

Disabled

Vehicle Speed Sensor

ALL

km/h

mph

0 km/h

(0 mph)

Scan Tool Data List Holden

The Engine Scan Tool Data List contains all engine related parameters that are available on the scan tool. The list is arranged in alphabetical order. A parameter may appear in any one of the data lists, and in some cases may appear more than once, or in more than one data list in order to group certain related parameters together.

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

    • The Diagnostic System Check - Engine Controls is completed.
    • There are no diagnostic trouble codes (DTCs).
    • The on-board diagnostics are functioning correctly.

Scan tool values from an engine that is operating correctly may be used for comparison with the engine you are diagnosing. The Engine Scan Tool Data List represents the values that would be seen on a normal operating engine.

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

Only the parameters listed below are referenced in this service information for use in diagnosis. If all values are within the typical range described below, refer to Symptoms - Engine Controls for diagnosis.

Scan Tool Parameter

System State

Expected Values

Description

Engine Idling/Radiator Hose Hot/Park or Neutral/Closed Loop/Accessories Off

A/C Pressure (Air Conditioning)

On

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 Pressure (Air Conditioning)

On

Off

kPa

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

A/C Relay (Air Conditioning)

On

Off

-

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

APP Sensor 1 (Accelerator Pedal Position)

-

0-5 Volts

This parameter displays the actual voltage of the accelerator pedal position (APP) sensor 1 signal circuit as measured by the control module.

APP Sensor 2 (Accelerator Pedal Position)

-

0-5 Volts

This parameter displays the actual voltage of the accelerator pedal position (APP) sensor 2 signal circuit as measured by the control module.

B1 Average Injection Time (Bank 1)

-

ms

This parameter displays the amount of fuel injector ON time or pulse width as commanded by the engine control module.

B1 Long Term Fuel Trim (Bank 1)

-

-50 to +50%

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

B1 Short Term Fuel Trim (Bank 1)

-

-50 to +50%

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

B1S1 O2 Sensor (Bank 1 Sensor 1)

-

0-1,006 mV

This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

B1S1 O2 Sensor Heater (Bank 1 Sensor 1)

-

0-100%

This parameter displays the % of the O2 sensor heater.

B1S2 O2 Sensor (Bank 1 Sensor 2)

-

0-1,006 mV

This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust

B1S2 O2 Sensor Heater (Bank 1 Sensor 2)

-

0-100%

This parameter displays the % of the O2 sensor heater.

B2 Average Injection Time (Bank 2)

-

ms

This parameter displays the amount of fuel injector ON time or pulse width as commanded by the engine control module.

B2 Long Term Fuel Trim (Bank 2)

-

-50 to +50%

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

B2 Short Term Fuel Trim (Bank 2)

-

-50 to +50%

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

B2 Short Term Fuel Trim (Bank 2)

-

-50 to +50%

This parameter displays percentage. This parameter indicates the average of the short term fuel trim cells. The short fuel trim cells are rated, or weighted for the amount of which they are used.

For example, the control module rates an idle cell higher then a wide open cell. If a fueling malfunction occurs in the idle cell and the wide open, the idle cell would effect more than the wide open cell. 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.

B2S1 O2 Sensor (Bank 2 Sensor 1)

-

0-1,006 mV

This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

B2S1 O2 Sensor Heater (Bank 2 Sensor 1)

-

%

This parameter displays the % of the O2 sensor heater.

B2S2 O2 Sensor (Bank 2 Sensor 2)

-

mV

This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

B2S2 O2 Sensor Heater (Bank 2 Sensor 2)

-

%

This parameter displays the % of the O2 sensor heater.

Barometric Pressure

-

65-104 kPa

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

Battery Voltage

On

Off

Battery Voltage

This parameter displays 0 to 30 Volts. The voltage measured between the module’s battery positive voltage circuit and ground circuit.

Coolant Temperature

-

-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.

Coolant Temperature

-

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.

Cooling Fan High Speed

On

Off

-

This parameter displays the control module commanded state of the high speed cooling fan relay.

Cooling Fan Low Speed

On

Off

-

This parameter displays the control module commanded state of the low speed cooling fan relay.

Cruise Control

Off

On

Resume

Accel

Set

Coast

-

This parameter displays the state of the on/off switch input to the control module . The scan tool will display On when the cruise ON/OFF switch is on. The scan tool will display OFF when the cruise ON/OFF switch is OFF.

Cruise Resume/Accel Switch: This parameter displays the state of the Resume/Accel switch input to the control module When the cruise control switch is in the on position and the Resume/Accel switch is activated, the scan tool displays On. When the Resume/Accel switch is released the scan tool displays Off.

Cruise Set/Coast Switch: This parameter displays the state of the Set/Coast switch input to the control module from the cruise control system. When the cruise control switch is in the on position and the Set/Coast switch is activated, the scan tool displays On. When the Set/Coast switch is released the scan tool displays Off.

Desired Engine Idle Speed

-

RPM

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

EGR Position Command (Exhaust- Gas Recirculation)

-

0-100%

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

EGR Position Feedback (Exhaust Gas Recirculation)

-

0-5 Volts

This parameter displays the actual EGR pintle position in volts.

Engine Runtime

-

h:m:s

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

Engine Speed

-

RPM

This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor.

EVAP Purge Solenoid (Evaporative Emission)

-

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.

Fuel Level Sensor

-

0-5 Volts

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

Fuel Level Sensor

-

0-100%

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

Fuel Pump Relay

Active

Inactive

-

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

Intake Air Temperature

-

-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.

Intake Air Temperature

-

0-5 Volts

This parameter displays the voltage intake air temperature (IAT) sensor.

Knock Retard Cylinder 1

-

°CA

This parameter indicates how much ignition spark timing is being retarded due to all control systems monitored by the engine control module. The scan tool will display a high value during extreme conditions such as high temperatures and antilock braking. The scan tool will display a lower value during lighter driving conditions.

Knock Retard Cylinder 2

-

Knock Retard Cylinder 3

-

Knock Retard Cylinder 4

-

Knock Retard Cylinder 5

-

Knock Retard Cylinder 6

-

MAP Sensor (Manifold Absolute Pressure)

-

kPa

This parameter displays the pressure from the manifold absolute pressure (MAP) sensor to the control module.

MAP Sensor (Manifold Absolute Pressure)

-

0-5 Volts

This parameter displays the signal voltage from the manifold absolute pressure (MAP) sensor to the control module.

Mass Air Flow Sensor

-

mg/strk

This parameter displays the measured quantity of air flowing into the engine during all operating conditions.

Spark

-

°

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.

Throttle Position PWM Servo Signal

-

%

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

Throttle Position Sensor

-

°

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

TP Sensor 1 (Throttle Position)

-

0-5 Volts

This parameter displays the actual voltage of the throttle position (TP) sensor 1 signal circuit as measured by the control module.

TP Sensor 2 (Throttle Position)

-

0-5 Volts

This parameter displays the actual voltage of the throttle position (TP) sensor 2 signal circuit as measured by the control module.

Vehicle Security Status

Learned

Learn Pending

No Immobilizer

Not Learned

-

This parameter displays the status of the vehicle theft deterrent system. The normal parameter display for the theft deterrent system is Learned.

Vehicle Speed

-

km/h

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

VIM Solenoid (Variable Intake Manifold)

Open

Closed

-

This parameter displays the engine control modules commanded state of the VIM solenoid.

VIM Solenoid (Variable Intake Manifold)

-

V

This parameter displays the voltage of the engine control modules commanded state of the VIM solenoid.