3X - E

The Scan Tool Data Definitions contain 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 appears more than once or in more than one data list in order to group certain related parameters together.

3X Crank Sensor: The scan tool displays 1,200-10,000 RPM. This signal is calculated from the 18X pulses and is fed to the powertrain control module (PCM) by the ignition control module (ICM). This is used by the PCM to calculate RPM at engine speeds above 1,200 RPM and to initiates injector pulses.

18X Crank Sensor: The scan tool displays 0-1,200 RPM. This signal is produced by the ignition control module (ICM) and is fed to the powertrain control module (PCM) to calculate engine RPM below 1,200 RPM.

1-2 Solenoid: The scan tool displays OK, Fault or Invalid state. These parameters describe the condition of the control circuit.

2-3 Solenoid: The scan tool displays OK, Fault or Invalid state. These parameters describe the condition of the control circuit.

A/C High Side Pressure Sensor: The scan tool displays 0.00-5.00 volts. Represents the A/C refrigerant pressure sensor signal. The amount of pressure indicates the amount of load that the A/C compressor is placing on the engine. The powertrain control module (PCM) uses this information to adjust idle and to control the cooling tans.

A/C OFF for WOT: A/C OFF for wide open throttle (WOT) indicated if A/C operation has been disabled due to a WOT condition. The scan tool displays YES or NO.

A/C Pressure Disable: The scan tool displays YES or NO. YES displayed indicated that the powertrain control module (PCM) is monitoring an A/C refrigerant pressure signal voltage which is too high or too low to allow the A/C compressor clutch to engage.

A/C Relay Circuit Status: The scan tool displays OK, Fault or Invalid state. These parameters describe the condition of the control circuit.

A/C Relay Command: A/C Relay Command indicates the commanded state of the A/C relay control circuit. The scan tool displays On or Off.

A/C Request Signal: The scan tool displays YES or NO. Indicates the state of the A/C request input circuit from the heating, ventilation, and air conditioning (HVAC) controls. The powertrain control module (PCM) uses the A/C request signal to determine whether A/C compressor operation is being requested.

Air/Fuel Ratio: The scan tool displays 0.0-25.5. The air/fuel ratio indicates the powertrain control module (PCM) commanded value. In Closed Loop, air/fuel ratio should normally be around 14.2-14.7. A lower air/fuel ratio indicates a richer commanded mixture, which may be seen during Power Enrichment or three-way converter (TWC) protection modes. A higher air/fuel ratio indicates a leaner commanded mixture. This can be seen during Decel Fuel Mode.

APP Average: The scan tool displays 0-150 counts. If the accelerator pedal is fully depressed the scan tool will display approximately 122 counts. The throttle actuator control (TAC) module takes the voltages from the 3 accelerator pedal position (APP) sensors, averages the readings and converts the readings into counts. The scan tool displays the average. The average is different on every vehicle.

APP Indicated Angle: The scan tool displays 0-100 percent. The scan tool displays the accelerator pedal position (APP) in percentage. If the APP is at rest, the display shows 0 percent. If the APP is fully depressed, the display shows 100 percent.

APP Sensor 1/2/3: The scan tool displays 0-5.0 volts. If the accelerator pedal is at 0 percent, or the pedal is at rest, the display shows approximately 1 volt. If the accelerator pedal is at 100 percent, or the pedal is fully depressed, the display shows approximately 3.6 volts.

APP Sensor 1/2/3: The scan tool displays 0-100 percent. If the accelerator pedal is at rest, display shows 0 percent. If the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the throttle actuator control (TAC) module the actual pedal position.

APP Sensor 1 and APP Sensor 2 Disagree: The scan tool displays Agree or Disagree. If the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 1 which is not in proper relationship to APP sensor 2, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

APP Sensor 1 and APP Sensor 3 Disagree: The scan tool displays Agree or Disagree. If the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 1 not in proper relationship to APP sensor 3, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

APP Sensor 2 and APP Sensor 3 Disagree: The scan tool displays Agree or Disagree. If the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 2 not in proper relationship to APP sensor 3, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

BARO: The scan tool displays 10-105 kPa (0-5 volts). The barometric pressure (BARO) reading is determined from the manifold absolute pressure (MAP) sensor signal monitored during key up and wide-open throttle (WOT) conditions. The BARO is used in order to adjust the fuel delivery, and to spark advance in order to compensate for altitude changes.

Clutch Pedal Switch: The scan tool displays APPLIED or RELEASED. The powertrain control module (PCM) monitors the clutch pedal switch input. If a low voltage is monitored, the PCM considers the clutch anticipate switch closed to ground, when the clutch pedal released. This is done to avoid a possible RPM flare caused by the sudden change in engine load.

CMP Sensor Signal Present: The scan tool displays YES or NO. If the powertrain control module (PCM) does not receive a cam signal from the ignition control module the scan tool displays NO

Cruise Control Active: The scan tool displays ENGAGED or DISENGAGED. This represents the state of the Cruise Status Input from the powertrain control module (PCM) module. The cruise should not display ENGAGED unless the vehicle is operating in cruise control.

Cruise Disengage 1-6 History: The scan tool displays the last 6 cruise control disengages in order from 1-6. There are 30 possible causes for the cruise control to disengage.

Cruise On/Off Switch: The scan tool displays ON or OFF. If you activate the cruise control switch, the scan tool displays ON. The switch, when in the ON position, sends a signal voltage to the throttle actuator control (TAC) module, that signal is then sent to the powertrain control module (PCM) across serial data. This allows all other functions of the cruise control. If you turn OFF the cruise control switch, the scan tool displays OFF.

Cruise Release Brake Pedal Switch: The scan tool displays RELEASED or APPLIED. This circuit has the cruise brake switch and the cruise clutch switch wired in series on manual transmission vehicles. This represents the position of the brake pedal and clutch as seen by the powertrain control module (PCM). If the brake or clutch pedal is applied the PCM will not allow the cruise to engage. If a fault occurs on this circuit known as the cruise control brake switch Circuit, DTC P0571 will set and cruise will not function.

Cruise Resume/Accel: The scan tool displays ON or OFF. If the cruise control switch is in the ON position and the Resume/Accel switch is activated, the scan tool displays ON. The switch, when in the ON position, sends a signal voltage to the throttle actuator control (TAC) module, that signal is then sent to the powertrain control module (PCM) across serial data. If the Resume/Accel switch is released the scan tool displays OFF.

Cruise Set/Coast: The scan tool displays ON or OFF. If the cruise control switch is in the ON position and the Set/Coast switch is activated, the scan tool displays ON. The switch, when in the ON position, sends a signal voltage to the throttle actuator control (TAC) module, that signal is then sent to the powertrain control module (PCM) across serial data. If the Set/Coast switch is released the scan tool displays OFF.

Current Gear: The scan tool displays 0-4. The scan tool display the gear that the transmission is in. An illegal transmission position displays 9.

Cycles of Misfire Data: Scan Tool Range 0-99 Counts. Indicates the total number of cylinder tiring events that were detected as being misfires during the last 200 crankshaft revolution sample period.

Cyl. 1-6 Injector Circuit History: Scan Tool Displays-Fault or OK. This parameter saves the state of the driver circuit for this device.

Cyl. 1-6 Injector Circuit Status: Scan Tool Displays-Fault or OK. This parameter indicates the state of the driver circuit for this device.

Decel Fuel Cutoff: The scan tool displays ACTIVE or INACTIVE. ACTIVE is displayed if the powertrain control module (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 (TP) has been detected while the vehicle is traveling over 40 km/h (25 mph). While in Deceleration Fuel mode, the PCM will decrease the amount of fuel delivered by entering Open Loop, and by decreasing the injector pulse width.

Desired EGR Position: The scan tool displays 0-100 percent. This represents the exhaust gas recirculation (EGR) pintle position that the powertrain control module (PCM) is commanding. Desired EGR position should stay close to actual EGR position.

Desired EGR Position: The scan tool displays 0-5 volts. This represents the exhaust gas recirculation (EGR) pintle position that the powertrain control module (PCM) is commanding. Desired EGR position should stay close to actual EGR position.

Desired Idle Speed: The scan tool displays 0-3187 RPM. This represents the idle speed that is commanded by the powertrain control module (PCM). The PCM will compensate for various engine loads based on engine coolant temperature (ECT) to keep the engine at the desired idle speed.

Driver Module 1/2/3/4 Status: The scan tool displays Enabled, Off-High volts, Off-High Temp or Invalid state. This parameter describes the internal powertrain control module (PCM) driver module condition. This module controls all the relays/solenoids listed below the Driver Module parameter in the scan tool Output Driver Data List up to the next driver module.

ECT Sensor: The scan tool displays -40 to +151°C (-40 to +304°F). The engine coolant temperature (ECT) sensor is mounted in the coolant stream. The powertrain control module (PCM) applies 5 volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. If the sensors internal resistance is high, the PCM monitors the signal voltage, and interprets the high voltage as a cold engine. As the sensors internal resistance decreases, the voltage signal decreases, and the PCM interprets the lower voltage as a warm engine.

EGR Flow Test Count: The scan tool displays 0-255 counts. This indicates the number of exhaust gas recirculation (EGR) flow test samples collected during the current ignition cycle. The maximum number of samples allowed is 1 during normal operation. If the powertrain control module (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 Learned Minimum Position: The scan tool displays 0-5 volts. This represents the learned voltage that the powertrain control module (PCM) uses to determine whether or not the exhaust gas recirculation (EGR) valve is fully closed, and at 0 percent pintle position. If the desired EGR position is 0 percent, 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 Position Sensor: The scan tool displays 0-100 percent. This represents the actual position of the exhaust gas recirculation (EGR) pintle in percent. Zero percent displayed indicates a fully extended pintle, and that the EGR valve is closed.

EGR Position Sensor: The scan tool displays 0-5 volts. Indicates the exhaust gas recirculation (EGR) pintle position sensor signal voltage being monitored by the powertrain control module (PCM). A low voltage indicates a fully extended pintle, and a closed valve. A voltage near 5 volts indicates a fully retracted pintle, or open valve.

EGR Position Variance: The scan tool displays 0-100 percent. Indicates the difference between desired exhaust gas recirculation (EGR) position and actual EGR position currently being monitored by the powertrain control module (PCM). If the EGR Position Error reaches an unacceptable level, DTC P1406 will set.

EGR Solenoid Circuit History: Scan Tool Displays-Fault or OK. This parameter saves the state of the driver circuit for this device.

EGR Solenoid Circuit Status: The scan tool displays OK, Fault or Invalid state. These parameters describe the condition of the control circuit.

EGR Solenoid Command: Exhaust gas recirculation (EGR) Solenoid Command indicates the EGR valve driver pulse width modulation (PWM) signal from the powertrain control module (PCM). A duty cycle of 0 percent indicates that an EGR flow is not being commanded. A 100 percent duty cycle indicates maximum EGR flow commanded.

Engine Load: The scan tool displays 0-100 percent. The engine load is calculated by the powertrain control module (PCM) from engine speed and mass air flow (MAF) sensor readings. Engine load should increase with an increase in RPM or air flow.

Engine Oil Level Switch: Engine Oil Level Switch indicates the electrical state of the switch. The scan tool displays OK or Low.

Engine Run Time: The scan tool displays 00:00:00-99:99:99 Hrs:Min:Sec. Indicates the time elapsed since the engine was started. If the engine is stopped, ENGINE RUN TIME will be reset to 00:00:00.

Engine Speed: The scan tool displays 0-9999 RPM. The engine speed is computed by the powertrain control module (PCM) from the 3X reference input. The engine speed should remain close to desired idle under various engine loads with engine idling.

EVAP Fault History: The scan tool displays NO FAULT, EXCESS VACUUM, PURGE VALVE LEAK, SMALL LEAK or WEAK VACUUM. The evaporative emission (EVAP) Fault History indicates the status of the EVAP system diagnostics performed by the powertrain control module (PCM).

EVAP Purge Solenoid Circuit Status: Evaporative emission (EVAP) Purge Solenoid Circuit Status indicates the condition of the control circuit. The scan tool displays OK, Fault or Invalid state.

EVAP Purge Solenoid Command: The scan tool displays 0-100 percent. This represents the powertrain control module (PCM) commanded pulse width modulation (PWM) duty cycle of the evaporative emission (EVAP) purge valve. Zero percent displayed indicates a lack of purge. A 100 percent displayed indicates full purge.

EVAP Test Abort Reason: Evaporative emission (EVAP) Test Abort Reason indicates the reason the EVAP test was aborted. The scan tool displays EXCESS VACUUM, PURGE VALVE LEAK, SMALL LEAK or WEAK VACUUM.

EVAP Test Result: Scan Tool Displays-No Results, Passed, Aborted, Fail DTC P0440, Fail DTC P0442, Fail DTC P0446, Fail DTC 1441. This information can be used to check system operation. This parameter displays the results of the evaporative emission (EVAP) system diagnostic tests.

EVAP Test State: Scan Tool Displays-Test Completed, Test Running, Wait for Purge. Indicates the current status of the evaporative emission (EVAP) diagnostic routine.

EVAP Vent Solenoid Command: The scan tool displays Not Venting or Venting. The scan tool displays Not Venting when the vent is commanded closed. The scan tool will show venting when the vent is commanded open.