The Engine Scan Tool Data Definitions contains a brief description of all engine related parameters available on the scan tool. The list is in alphabetical order. A given parameter may appear in any one of the data lists. In some cases, the parameter may appear more than once or in more than one data list in order to group certain related parameters together.

1-2 Sol.: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

2-3 Sol.: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

24X Crank Sensor (Data): The scan tool displays 0-1750 RPM. This parameter is engine RPM calculated from CKP sensor data. Due to the resolution of the signal, this data is limited to the idle RPM range.

A/C High Side Pressure: The scan tool displays 0.00-5.00 Volts. This parameter represents the A/C refrigerant pressure sensor signal. The amount of pressure indicates the amount of load that the A/C compressor places on the engine. The PCM uses this information in order to adjust idle and in order to control the cooling fans.

A/C High Side Pressure: The scan tool displays -103 to +3119 kPa, -14 to +452 psi. This parameter represents the A/C refrigerant pressure sensor voltage signal converted to pressure.

A/C Off For WOT: The scan tool displays Yes or No. Yes indicates that the PCM has disabled the A/C compressor because the TP sensor signal is at wide open throttle.

A/C Pressure Disable: The scan tool displays Yes or No. Yes indicates that the PCM has disabled the A/C compressor due to excessive refrigerant pressure.

A/C Relay: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

A/C Request: The scan tool displays Yes or No. The A/C Request indicates the state of the A/C request input circuit from the HVAC controls. The PCM uses the A/C request signal in order to determine whether the A/C compressor operation is being requested.

AIR Pump Relay: The scan tool displays On or Off. When the PCM grounds the AIR pump relay control circuit, the scan tool indicates ON. When the PCM disables the ground circuit, the scan tool indicates Off.

AIR Solenoid: The scan tool displays On or Off. When the PCM grounds the AIR pump solenoid control circuit, the scan tool indicates ON. When the PCM disables the ground circuit, the scan tool indicates Off.

Abuse Management: The scan tool indicates Active or Inactive. This parameter will indicate Active when the PCM determines that excessive stress is being applied to the powertrain. The PCM is reducing engine torque when Active is displayed.

Actual EGR Position: The scan tool range is 0-100 percent. Represents the actual position of the EGR pintle in percent. 0percent displayed indicates a fully extended pintle (EGR valve closed).

Air Fuel Ratio: The scan tool displays the ratio of air to fuel in terms of mass. A typical ratio is 14.7:1.

BARO: The scan tool range is 10-105 kPa or 0.00-5.00 Volts. The Barometric Pressure reading is determined from the MAP sensor signal. The PCM monitors the MAP signal during key up and Wide-Open Throttle (WOT) conditions. The Barometric Pressure compensates for altitude differences.

Brake Switch: The scan tool displays Applied or Released. This parameter indicates the state of the brake switch circuit input. Open indicates 0.0 voltage input (brake switch open, brake pedal applied). Closed indicates a B+ voltage input (brake switch closed, brake pedal released). When you apply the vehicle brakes, the scan tool display shows Applied. The torque converter clutch and cruise control disengages. When you release the vehicle brakes, the scan tool displays Released. This allows the cruise control to be resumed and the torque converter clutch to engage.

CKP Sensor Status: The scan tool displays Angle, Time A or Time B. During normal operation the PCM calculates crankshaft position in an angle based mode using the signals from both CKP sensors. If there is a problem with one of the signals, the PCM will switch to a time based calculation and the scan tool will indicate which signal is being used.

CMP Sensor (Data): The scan tool displays RPM. This parameter is engine RPM calculated from the CMP sensor signal.

Cam Signal Present: The scan tool displays Yes or No. This parameter indicates whether or not the PCM is receiving CMP sensor pulses.

Commanded A/C: The scan tool displays On or Off. Represents the PCM commanded state of the A/C compressor clutch relay driver circuit. The A/C compressor clutch should be engaged when Commanded A/C displays On.

Commanded Fuel Pump: The scan tool displays On or Off. Represents the PCM commanded state of the fuel pump relay driver circuit.

Commanded GEN: The scan tool displays On or Off. Off displayed indicates that the PCM has commanded the generator control circuit Off.

Crank Request: The scan tool displays Yes or No. Yes is displayed when the key is in the Crank position.

Cruise Inhibited: The scan tool displays Yes or No. Yes displayed indicates that the PCM is commanding the SMCC module to inhibit cruise control operation. Should display Yes with park, neutral, reverse or low gear selected.

Cruise Inhibited: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Cruise Mode: The scan tool displays On or Off. On indicates that Cruise is engaged.

Current Gear: The scan tool displays the numbers 1, 2, 3, or 4. The PCM looks at Trans Range position and the gear commanded by the PCM. The actual forward gear that the Transaxle is in will be the lower of the two because the manual valve can override the PCM commanded gear. The scan tool displays which gear the transmission is in. The scan tool displays 9 if the transmission gear is unknown.

Cycles Of Misfire Data: The display shows counts from 0-100. This parameter displays which engine cycle of the 100 engine cycle test that the PCM is collecting data for DTC P0300.

Cyl. #1 IC Circuit Status - Cyl. #6 IC Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Cyl. #1 Injector Ckt. Status - Cyl. #6 Injector Ckt. Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Decel Fuel Mode: The scan tool displays Active or Inactive. Active displayed indicates that the PCM has detected conditions appropriate to operate in Deceleration Fuel Mode. The PCM will command deceleration fuel mode when a sudden decrease in throttle position has been detected while the vehicle is traveling over 10 mph. While in Deceleration Fuel mode, the PCM will decrease the amount of fuel delivered by entering Open Loop and decreasing the injector pulse width.

Desired Idle Speed: The scan tool range is 0-3187 RPM. The PCM commands the desired idle speed. The PCM compensates for various engine loads based on engine coolant temperature in order to keep the engine at the desired speed.

Desired EGR Position: The scan tool range is 0-100 percent. Represents the EGR pintle position that the PCM is commanding. Desired EGR Position should stay close to Actual EGR Position.

Driver Module 1 Status - Driver Module 4 Status: The scan tool displays Enabled, Off - High Volts or Off - High Temp. This indicates the current state of each driver module.

ECT: The scan tool range is -39°C to +140°C (-38°F to +284°F). The PCM applies 5 volts to the ECT sensor circuit. The sensor is a thermistor that changes internal resistance as temperature changes. When the sensor is cold (internal resistance high), the PCM monitors a high signal voltage and interprets the voltage as a cold engine. As the sensor warms (internal resistance decreases), the voltage signal decreases and the PCM interprets the lower voltage as a warm engine.

EGR Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

EGR Circuit History: The scan tool displays OK or Fault. This parameter saves the state of the driver circuit for this device.

EGR Closed Pintle Position: The scan tool range is 0-255 counts. This value is the closed valve position in counts.

EGR Closed Val. Pintle Position: The scan tool range is 0.0-5.0 Volts. Represents the learned voltage that the PCM uses to determine whether or not the EGR valve is fully closed (0 percent pintle position). If the Desired EGR Position is 0percent and a difference of more than 0.4 volt between EGR Feedback and EGR Closed Valve Pintle Position is detected, DTC P1406 will set.

EGR Duty Cycle: The scan tool range is 0-100 percent. Represents the EGR valve driver PWM signal from the PCM. A duty cycle of 0 percent indicates that no EGR flow is being commanded; a 100 percent duty cycle indicates maximum EGR flow commanded.

EGR Feedback: The scan tool range is 0.00-5.00 Volts. Indicates the EGR pintle position sensor signal voltage being monitored by the PCM. A low voltage indicates a fully extended pintle (closed valve); a voltage near 5  volts indicates a fully retracted pintle (open valve).

EGR Flow Test Count: The scan tool range is 0-255 counts. Indicates the number of EGR flow test samples collected during the current ignition cycle. The maximum number of samples allowed is 1 during normal operation. If the PCM battery feed has been disconnected or a DTC P0401 has been cleared, several EGR flow test samples will be allowed during the next ignition cycle. This is to allow repair verification during a single ignition cycle.

EGR Position Error: The scan tool range is -100 percent to +100 percent. Indicates the difference between Desired EGR Position and Actual EGR Position currently being monitored by the PCM. If the EGR Position Error reaches an unacceptable level, DTC P0404 or P1404 will set.

EVAP Canister Purge: The scan tool range is 0-100 percent. Represents the PCM commanded PWM duty cycle of the EVAP Purge valve. 0percent displayed indicates no purge; 100percent displayed indicates full purge.

EVAP Fault History: The scan tool displays No Fault, Excess Vacuum, Purge Valve Leak, Small Leak or Weak Vacuum. This parameter displays the result of the EVAP system diagnostic.

EVAP Purge Sol.: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

EVAP Test Result: The scan tool displays No Result, Passed, Aborted, Fail - DTC P0440, Fail - DTC P0442, Fail - DTC P0446, Fail - DTC P1441. This information can be used to check system operation. Operate the vehicle within the conditions required to enable the diagnostic (refer to the EVAP DTCs supporting text). This parameter displays the results of the EVAP system diagnostic tests.

EVAP Test Result Reason: The scan tool displays Not Aborted, Lost Enable, Small Leak, Vehicle Not At Rest. Provides additional information relative to the EVAP Test Result parameter.

EVAP Test State: The scan tool displays Wait For Purge, Test Running, Test Completed. Indicates the current status of the EVAP diagnostic routine.

EVAP Vent Sol.: The scan tool displays Open or Closed. Represents the state of the EVAP Canister fresh air vent solenoid. Should be open during normal operation.

Engine Load: The scan tool range is 0-100 percent. The PCM calculates the Engine load from engine speed and MAF sensor readings. The Engine Load increases with an increase in RPM or airflow.

Engine Oil Pressure: The scan tool displays OK or Low. The scan tool displays whether or not there is sufficient engine oil pressure.

Engine Run Time: The scan tool displays Hours, Minutes, Seconds. This indicates the amount of engine run time. When the ignition is cycled off, the timer will reset to zero.

Engine Speed: The scan tool range is 0-10000 RPM. The PCM computes Engine speed from the ignition reference pulses. The Engine speed should remain close to desired idle under various engine loads with the engine idling.

FC Relay 1: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

FC Relay 2 and 3: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Fans High Speed: The scan tool displays On or Off. The PCM is commanding all three fan control relays on when the scan tool indicates On. When all fan control relays are activated, both cooling fans are enabled on high speed.

Fans Low Speed: The scan tool displays On or Off. The PCM is commanding Fan Control relay 1 On when the scan tool indicates On. When the PCM commands the Fan Control relay 1 On, both fans are enabled on low speed.

Fuel Level: The scan tool displays 5.00 to 0 Volts. The PCM supplies a 5 volt signal circuit to the fuel level sensor. The float inside the fuel tank is connected to a variable resistor which causes the signal voltage to change with fuel level. The PCM converts the signal voltage to a fuel level value. The scan tool displays close to 0.8 volts for an empty tank, and close to 2.5 volts for a full tank.

Fuel Pump Ckt. Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Fuel Pump Ckt. History: The scan tool displays OK or Fault. This parameter saves the state of the driver circuit for this device.

Fuel Tank Pressure: The scan tool displays -17.5 to +7.5 in. H2O or -32.7 to +14.0 mmHg. Fuel Tank Pressure is used extensively for EVAP purge control and EVAP system diagnostics.

Fuel Tank Pressure: The scan tool displays 0 to 5 volts. Fuel Tank Pressure is used extensively for EVAP purge control and EVAP system diagnostics.

Fuel Trim Cell: The scan tool range is 0-9. The fuel trim cell is dependent upon the engine speed and the MAF sensor readings. A plot of RPM vs. MAF is divided into 10 cells. The fuel trim cell indicates which cell is currently active.

Fuel Trim Learn: The scan tool displays Enabled or Disabled. When conditions are appropriate for enabling long term fuel trim corrections, the scan tool displays Enabled. This indicates that the long term fuel trim is responding to the 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.

Generator PWM: The scan tool displays 0-100 percent. This parameter indicates the pulse width of the voltage regulator's generator field control circuit. A high value indicates high electrical load.

HO2S Sensor 1: The scan tool displays Not Ready or Ready. Indicates the status of the fuel control exhaust oxygen sensor. The scan tool will indicate that the exhaust oxygen sensor is ready when the PCM detects a fluctuating HO2S voltage sufficient to allow closed loop operation. This will not occur unless the exhaust oxygen sensor is warmed up.

HO2S Sensor 1: The scan tool range is 0-1000 mV. The HO2S Bn1 sensor 1 parameter represents the fuel control exhaust oxygen sensor output voltage. The voltage should fluctuate constantly within a range between about 50 mV (lean exhaust) and 800 mV (rich exhaust) while operating in Closed Loop.

HO2S Sensor 2: The scan tool range is 0-1000 mV. The HO2S Bn1 Sensor 2 parameter is the post-catalyst exhaust oxygen sensor output voltage. Voltage should fluctuate within a range between about 50 mV (lean exhaust) and 800 mV (rich exhaust) while operating in Closed Loop. The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control HO2S. This is due to the oxygen storage capability of an efficiently operating catalyst. If the voltage is fluctuating rapidly, and the catalyst is hot, low catalyst efficiency may be the cause.

HO2S XCounts: The scan tool range is 0-255. This figure indicates the number of times the HO2S 1 signal has crossed the 450 mV bias voltage during a 1 second interval. A HO2S 1 signal that almost never crosses the bias voltage could indicate a fuel trim problem, a faulty HO2S 1 circuit, or a faulty HO2S 1.

Hot Mode: The scan tool displays On or Off. The PCM has the ability to disable 3 injectors during an engine overtemperature condition. The engine enters this mode of operation if the ECT reaches 131°C (268°F). This protection mode permits the PCM to alternate between groups of 3 cylinders, thereby reducing engine temperature. On indicates that the engine is operating in the alternating 3 cylinder mode.

Hot Open Loop: The scan tool displays Inactive or Active. Active indicates that the PCM has commanded open loop operation due to high engine temperature.

IAC Position: The scan tool range is 0-255 counts. Displays the commanded position of the idle air control pintle in counts. A larger number of counts means that more air is being commanded through the idle air passage. IAC Position should respond fairly quickly to changes in engine load to maintain desired idle RPM.

IAT: The scan tool range is -39°C to +140°C (-38°F to 284°F). The PCM converts the resistance of the intake air temperature sensor to degrees. The PCM uses the Intake Air Temperature (IAT) in order to adjust fuel delivery and spark timing according to incoming air density.

Ignition 1: The scan tool displays 0-25.5 Volts. The Ignition 1 represents the system voltage measured by the PCM at its ignition feed.

Injector Pulse Width: The scan tool range is 0-1000 msec. Indicates the amount of time the PCM is commanding each injector on during each engine cycle. A longer injector pulse width will cause more fuel to be delivered. Injector Pulse Width should increase with increased engine load.

Knock Retard: The scan tool range is 0-16 degrees. Knock Retard indicates the amount of spark the PCM removes from the IC spark advance in response to signals from the Knock sensor.

Long Term FT: The scan tool displays -100 percent to +100 percent. The PCM derives the Long Term Fuel Trim from the Short Term Fuel Trim value. The Long Term Fuel Trim represents a long-term correction of fuel delivery. A value of 0percent indicates that fuel delivery requires no compensation in order to maintain the PCM commanded air/fuel ratio. A negative value significantly below 0percent indicates that the fuel system is rich and the PCM is reducing the fuel delivery (decreased injector pulse width). A positive value significantly greater than 0percent indicates that a lean condition exists and the PCM compensates by adding fuel (increased injector pulse width). Fuel trim values at maximum authority may indicate an excessively rich or lean system.

Loop Status: The scan tool displays Open or Closed. Closed Loop indicates that the PCM is controlling fuel delivery according to oxygen sensor voltage. In Open Loop, the PCM ignores the oxygen sensor voltage and bases the amount of fuel to be delivered on TP sensor, engine coolant, and MAF sensor inputs only.

MAF: The scan tool range is 0.0-655 gm/s. MAF (Mass Air Flow) is the MAF Input Frequency converted to grams of air per second. This indicates the amount of air entering the engine.

MAF Frequency: The scan tool displays 0-31999 Hz. The PCM converts current draw needed by the MAF (to keep the hot wires at a constant temperature) into a frequency signal. The scan tool displays this frequency in Hertz.

MAP: The scan tool range is 10-105 kPa / 0.0 to 5.0 Volts. The Manifold Absolute Pressure (MAP) sensor measures the change in the intake manifold pressure from engine load, and speed changes. As intake manifold pressure increases, the intake vacuum decreases resulting in a higher MAP sensor voltage and kPa reading. The PCM uses the MAP sensor signal for the following: (1) Updating the BARO reading; (2) Enabling factor for several of the diagnostics.

MIL: The scan tool displays On or Off. The scan tool indicates if the PCM is commanding the Malfunction Indicator Lamp (MIL) on.

Misfire Current Cyl. #1 - Misfire Current Cyl. #6: The scan tool range is 0-255 counts. The Misfire Current counters increment at a rate according to the number of possible misfires the PCM detects on each cylinder during the last 200 cylinder firing events. The counters may normally display some activity, but the activity should be nearly equal for all the cylinders.

Misfire History Cyl. #1 - Misfire History Cyl. #6: The scan tool range is 0-65535 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.

Non Volatile Memory: The scan tool indicates Pass or Fail. This parameter indicates the results of a PCM internal test.

O2 Heater Current: The scan tool displays HO2S Heater Current in Amps. This parameter displays the current draw of the HO2S 1 heater only. Typically, the HO2S heater current stabilizes at about 0.50A to 0.60A after operating temperature is reached. Initial current draw is slightly higher.

Power Enrichment: The scan tool displays Active or Inactive. Active indicates that the PCM has detected conditions appropriate to operate in Power Enrichment mode. The PCM will command Power Enrichment mode when a large increase in throttle position and load is detected. While in Power Enrichment, the PCM will increase the amount of fuel delivered by entering Open Loop and increasing the injector pulse width. This is done to prevent a possible sag or hesitation from occurring during acceleration.

Short Term FT: The scan tool displays -100 percent to +100 percent. The Short Term Fuel Trim represents a short-term correction to fuel delivery by the PCM in response to the amount of time the fuel control oxygen sensor voltage spends above or below the 450 mV threshold. If the oxygen sensor voltage mainly remains less than 450 mV, indicating a lean air/fuel mixture, short term fuel trim increases into the positive range above 0percent. The PCM adds fuel. If the oxygen sensor voltage stays mainly above the threshold, the short term fuel trim decreases below 0percent into the negative range. The PCM reduces the fuel delivery in order to compensate for the indicated rich condition. Under certain conditions such as an extended idle and a high ambient temperature, the canister purge may cause the Short Term Fuel Trim to read in the negative range during normal operation. The Fuel trim values at maximum authority may indicate an excessively rich or lean system.

Spark: The scan tool range is -64 degrees to +64 degrees. Displays the amount of spark advance the PCM is commanding. The PCM computes spark advance using coolant temperature, RPM, engine load, vehicle speed, and requests for timing retard (from the KS system, TCS etc.). The PCM controls the timing and sequencing of the ignition system.

Start Up ECT: The scan tool range is -40°C to +151°C ( -40°F to +304°F). Indicates the engine coolant temperature at the time that the vehicle was started. Used by the HO2S diagnostic to determine if the last startup was a cold start.

Start Up IAT: The scan tool range is -40°C to +151°C ( -40°F to +304°F). Indicates the Intake Air Temperature at the time that the vehicle was started. Used by the HO2S diagnostic to determine if the last startup was a cold start.

Starter Enable Relay: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Starter Relay Status: The scan tool displays On or Off. Off indicates that the PCM is not allowing starter operation due to the engine running, excessive cranking time, trans not in P/N or other factors.

TCC Sol.: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

TCM Calibration ID: This parameter provides an additional identification number for internal PCM calibrations. Unless this information is specifically requested, the regular PCM Calibration ID part number (under ID Information) should be used.

TCM Software ID: This parameter provides an additional identification number for internal PCM software. Unless this information is specifically requested, the regular PCM Calibration ID part number (under ID Information) should be used.

TCS Status: The scan tool displays Active, Allowed, Inhibited, Comm. Link Fail, Trac PWM Input or Diag. Trac. PWM. Active indicates that a Traction Control event is occurring. Allowed indicates that the system is ready and operational but not currently controlling traction. Inhibited indicates that system operation is not allowed due to driver input or other factors. The remaining statuses indicate various malfunctions.

TCS Circuit Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

TCS Circuit History: The scan tool displays OK or Fault. This parameter saves the state of the driver circuit for this device.

TP Angle: The scan tool displays 0-100 percent. This parameter displays the amount of throttle opening in percent.

TP Sensor: The scan tool displays 0-5 Volts. The scan tool displays the amount of throttle opening in volts. Closed throttle displays about 1 Volt and wide open throttle displays about 3.5 Volts.

TR Switch P / A / B / C: The scan tool displays High or Low. The TR Switch P / A / B / C display represents the states of the four inputs from the transaxle range switch. High displayed indicates a B+ voltage signal being monitored at the PCM, Low displayed indicates a grounded input signal. A unique combination of transaxle range inputs represents each position of the transaxle manual valve.

TWC Protection: The scan tool displays Active or Inactive. Active displayed indicates that the PCM has detected conditions appropriate to operate in TWC Protection mode. This is determined based on Engine Load and Engine Coolant Temperature. While in TWC Protection, the PCM will decrease Air/Fuel Ratio to a value that depends on Mass Air Flow (higher Mass Airflow = lower Air/Fuel Ratio).

Tachometer Ckt. Status: The scan tool displays OK or Fault. This parameter indicates the state of the driver circuit for this device.

Tachometer Ckt. History: The scan tool displays OK or Fault. This parameter saves the state of the driver circuit for this device.

Total Misfire Current Count: The scan tool range is 0- 99 Counts. Indicates the total number of cylinder firing events that were detected as being misfires during the last 200 crankshaft revolution sample period.

Total Misfire Failures Since First Fail: The scan tool range is 0 to 65535 Counts. Indicates the number of 200 crankshaft revolution sample periods during which the level of misfire was sufficiently high to report a failure.

Total Misfire Passes Since First Fail: The scan tool range is 0 to 65535 Counts. Indicates the number of 200 crankshaft revolution sample periods during which the level of misfire was sufficiently low to report a pass.

Traction Control: The scan tool displays Active or Inactive. The scan tool displays active if the PCM receives a signal from the Electronic Brake and Traction control Module (EBTCM) requesting torque reduction during a traction control event.

Transmission Range: The scan tool displays the transaxle gear position.

VTD Fuel Disable: The scan tool displays Active or Inactive. If the PCM has not received the correct password from the Body Control Module (BCM), the PCM will disable the fuel system, and Active will be displayed on the scan tool. The scan tool displays Inactive under normal running conditions.

Vehicle Speed: The scan tool displays km/h and mph. The vehicle speed sensor signal is converted into km/h and mph for display.