For 1990-2009 cars

The Scan Tool Data Definitions list contains a brief description of all of the engine related parameters that are available on the scan tool. 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.

A/C Relay Command: This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.
APP Indicated Angle: 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: This parameter displays the actual voltage on the accelerator pedal position (APP) sensor 1 signal circuit as measured by the control module.
APP Sensor 2: This parameter displays the actual voltage on the accelerator pedal position (APP) sensor 2 signal circuit as measured by the control module.
APP Sensor 1 and 2: This parameter displays Disagree if the control module detects the signal voltage from APP sensor 1 is not in correct relationship to APP sensor 2. The scan tool displays Agree under normal operating conditions.
BARO: This parameter displays the barometric pressure. The control module uses the barometric pressure for fuel control to compensate for altitude differences.
BARO: This parameter displays the barometric pressure voltage. The control module uses the barometric pressure for fuel control to compensate for altitude differences.
Brake Pedal Signal Status: This parameter displays the serial data message of the brake signal from the EBTCM.
Calc. TWC Temp. Bank 1 or Bank 2: This parameter displays the catalytic converter temperature as calculated by the control module.
Catalytic Converter Protection Active: This parameter displays if the control module is commanding catalytic converter protection.
CKP Resync Counter: This parameter displays the number of times the control module re-syncs with the CKP sensor.
Commanded Air/Fuel Ratio and Equivalence Ratio: This parameter displays the ratio of air to fuel as calculated by the control module based on various sensor inputs. The scan tool will display a lower air fuel ratio when a richer air to fuel mixture is commanded. The scan tool will display a high air fuel ratio when a lean air to fuel mixture is commanded. During the Closed Loop operation, the air/fuel ratio is typically 14.2-14.7 to 1.
Cruise Control Active: This parameter displays the status of the cruise control system as determined by the control module.
Cycles of Misfire Data: This parameter displays the number of misfire tests during 200 engine revolutions.
Cylinder 1-6 Ignition Control Circuit Status: This parameter displays the diagnostic state of the output driver for the ignition control circuits. The scan tool will display Ok if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.
Cylinder 1-6 Injector Circuit Status: This parameter displays the state of the fuel injector control circuit. The parameter displays Fault if the fuel injector control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the control circuit has been commanded ON.
Cylinder 1-6 Knock Retard: This parameter displays the amount of cylinder 1-6 knock retard commanded by the control module. Each cylinder is controlled individually based on both knock sensor signal inputs.
Decel. Fuel Cutoff: This parameter displays the status of the operating mode of the control module used to turn Off the fuel injectors and the evaporative emission (EVAP) canister purge valve during certain deceleration conditions.
Desired Exh. CMP Bank 1 or 2: This parameter displays the desired exhaust camshaft angle as commanded by the control module.
Desired Heated Oxygen Sensor (HO2S) - Bank 1 or 2 Sensor 1: This parameter displays the desired HO2S lambda value as commanded by the control module.
Desired Idle Speed: This parameter displays the desired engine idle speed as commanded by the control module.
Desired Int. CMP - Bank 1 or 2: This parameter displays the desired intake camshaft angle as commanded by the control module.
DTC Set This Ignition : This parameter displays Yes if a DTC set on the current ignition cycle.
EC Ignition Relay Circuit Status: The scan tool displays Fault/Ok/Invalid State. The scan tool displays Fault until the ignition switch is turned to START position, then OK is displayed.
EC Ignition Relay Command: This parameter displays the state of the control circuit for control module power relay as commanded by the control module.
EC Ignition Relay Feedback Signal: This parameter displays the voltage available at the EC ignition relay pin of the control module.
ECM Reset: This parameter displays Yes when an internal control module reset occurs. The scan tool displays NO under normal operating conditions.
ECT Sensor: This parameter displays the temperature of the engine coolant based on input to the control module from the engine coolant temperature (ECT) sensor.
Engine Load: This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.
Engine Off EVAP Test Conditions Met: This parameter displays Yes if the conditions for running the Engine Off EVAP diagnostic are met.
Engine Off Time: This parameter displays the amount of time that has elapsed since the engine was last cycled OFF.
Engine Oil Level Switch: This parameter displays if the level of the engine oil is within range as determined by the control module from information received from the engine oil level switch.
Engine Oil Life Remaining: This parameter displays the percent of engine oil life remaining. The controller calculates the engine oil life by monitoring engine load, coolant temperature, and engine speed.
Engine Oil Pressure Sensor: The scan tool displays OK or Low. The ECM monitors the engine oil pressure switch and receives serial data message indicating the engine oil pressure condition.
Engine Oil Pressure Sensor: This parameter displays the voltage signal received by the control module from the engine oil pressure (EOP) sensor.
Engine Oil Temperature Sensor: This parameter displays the temperature of the engine oil as calculated by the control module using a signal from the engine oil temperature sensor. The engine oil temperature sensor has a range of values indicating a low value when the oil temperature is low to a high value when the oil temperature is high.
Engine Run Time: This parameter displays the time elapsed since the engine was started.
Engine Speed: This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a crankshaft position (CKP) sensor DTC, the engine control module (ECM) calculates the engine speed from one of the camshaft position (CMP) sensors.
EVAP Purge Solenoid Circuit Status: This parameter displays the state of the evaporative emission (EVAP) purge solenoid control circuit. The parameter displays Fault if the evaporative emission (EVAP) purge solenoid control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
EVAP Purge Solenoid Command: 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 Circuit Status: This parameter displays the state of the evaporative emission vent solenoid control circuit. The parameter displays Fault if the evaporative emission (EVAP) vent solenoid control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
EVAP Vent Solenoid Command: This parameter displays the state of the control circuit for evaporative emission (EVAP) vent solenoid as commanded by the control module.
Exh. CMP Angle Bank 1 or 2: This parameter displays the actual exhaust camshaft position in degrees.
Exh. CMP Bank 1 or 2 Command: This parameter displays the exhaust camshaft position in percent of range as commanded by the control module.
Exh. CMP Solenoid - Bn. 1 or 2 Circuit Status: This parameter displays the state of the exhaust camshaft actuator solenoid control circuit. The parameter displays Fault if the camshaft actuator solenoid control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
Fuel Level: This parameter displays the amount of fuel in the fuel tank in percent of range, as calculated by the control module.
Fuel Level Sensor Left Tank (Secondary): This parameter displays the voltage signal received by the control module from the left or secondary fuel level sensor.
Fuel Level Sensor Right Tank (Primary): This parameter displays the voltage signal received by the control module from the right or primary fuel level sensor.
Fuel Pump Relay Circuit Status: This parameter displays the state of the fuel pump relay control circuit. The parameter displays Fault if the fuel pump relay control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
Fuel Pump Relay Command: This parameter displays the control modules commanded state of the fuel pump relay control circuit.
Fuel Tank Level Remaining: This parameter displays the amount of fuel in liters/gallons that remains in the fuel tank as determined by the control module from information received from the left and right fuel level sensors.
Fuel Tank Pressure Sensor: 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: This parameter displays the voltage signal received by the control module from the fuel tank pressure (FTP) sensor.
Fuel Tank Rated Capacity: This parameter displays the capacity of the fuel tank in liters or gallons.
Fuel Trim Learn: 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 - Bank 1 or 2 Sensor 1: This parameter displays the lambda output from the heated oxygen sensor (HO2S) to the control module. A lambda below 1.0 indicates a rich exhaust, while a lambda above 1.0 indicates a lean exhaust.
HO2S - Bank 1 or 2 Sensor 2: 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.
HO2S Htr. Bn. 1 or 2 Sensor 1 or 2 Circuit Status: This parameter displays the state of the oxygen sensor heater control circuit. The parameter displays Fault if the oxygen sensor heater control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
HO2S Htr. Bn. 1 or 2 Sensor 1 or 2 Command: This parameter displays the commanded state of the heater control circuit as commanded by the control module.
HO2S Sensing Element - Bn. 1 or 2 Sensor 1: This parameter displays the resistance of the sensing element within the control module. The front sensors are normally regulated to 80 ohms.
HO2S 1 Module Signal (Bank 1 or Bank 2 Sensor 1): This parameter displays the HO2S transistor voltage in the engine control module.
IAT Sensor: 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 0 Signal: This parameter displays On when the control module detects a voltage at the ignition 0 input terminal.
Ignition 1 Signal: This parameter displays the ignition 1 signal voltage in the engine control module.
Ignition 1 Signal: This parameter displays On when the control module detects a voltage at the ignition 1 input terminal.
Spark Advance: This parameter displays spark advance in degrees.
IMRC Solenoid Circuit Status: This parameter displays the state of the intake manifold runner control (IMRC) control circuit. The parameter displays Fault if the intake manifold runner control (IMRC) control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
IMRC Solenoid Command: This parameter displays the control modules commanded state of the intake manifold runner control (IMRC) solenoid.
Initial Brake Apply Signal: This parameter displays the state of the brake pedal that is transmitted over the serial data circuit from the electronic brake control module (EBCM).
Injector 1-6 Command: This parameter displays the amount of fuel injector ON time or pulse width as commanded by the control module.
IAT CMP Angle - Bank 1 or 2: This parameter displays the actual intake camshaft position in degrees.
Int. Camshaft Position (CMP) Angle Bank 1 or 2: This parameter displays the difference between the desired intake camshaft position and the actual intake camshaft position.
IAT CMP - Bank 1 or 2 Command: This parameter displays the intake camshaft position in percent of range as commanded by the control module.
IAT CMP Solenoid - Bn. 1 or 2 Circuit Status: This parameter displays the state of the intake camshaft actuator solenoid control circuit. The parameter displays Fault if the camshaft actuator solenoid control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
Knock Retard: 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 1 or 2 Signal: This parameters displays the voltage input to the control module from the knock sensor (KS).
Loop Status - Bn. 1 or 2 Sen. 1: 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.
Loop Status - Bn. 1 or 2 Sen. 2: This parameter displays the state of the rear heated oxygen sensors as commanded by the control module. The rear sensors will not go into Closed Loop until the ECM determines that the HO2S is ready for operation.
LT FT - Bn. 1 or Bn. 2 Cruise/Accel.: This parameter displays the commanded Long Term Fuel Trim correction by the control module for bank 1 or bank 2 for cruise and acceleration conditions.
LT FT - Bn. 1 or Bn. 2 Idle/Decel.: This parameter displays the commanded Long Term Fuel Trim correction by the control module for bank 1 or bank 2 for idle and deceleration conditions.
MAF Sensor: This parameter displays the measured quantity of air flowing into the engine during all operating conditions.
MAF Sensor: This parameter displays the signal voltage from the mass air flow (MAF) sensor to the control module.
MIL Circuit Status: This parameter displays the state of the MIL control circuit. The parameter displays Fault if the MIL control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
MIL Command: This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit by the control module.
MIL Requested by DTC: This parameter indicates the reason the control module illuminated the MIL. The scan tool will display YES when the MIL is requested as a result of an A or B type DTC. The scan tool will display NO if the MIL is illuminated for another reason, such as transmission DTCs.
Mileage Since DTC Cleared: This parameter displays the mileage that has elapsed since any diagnostic trouble code (DTC) has been cleared from the control modules memory.
Misfire Current Cyl. 1-6: The scan tool displays a range of 0-200 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 History Cyl. 1-6: The scan tool displays a range of 0-65,535 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.
Moderate Brake Apply Signal: This parameter displays the state of the brake pedal that is transmitted over the serial data circuit from the electronic brake control module (EBCM).
PNP Switch: This parameter displays whether the transmission range selector is in park or neutral.
Power Enrichment: This parameter displays the status of the operating mode of the control module used to increase fuel delivery during certain acceleration conditions.
Reduced Engine Power: This parameter displays whether the control module is commanding reduced engine power due to a throttle actuator control (TAC) system condition.
Short Term FT - Bank 1 or Bank 2: This parameter displays the short-term correction to the fuel delivery by the control module in response to the oxygen sensor 1 or 2. 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: 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: 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: 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.
Stoplamp Pedal Switch: This parameter displays the position of the stop lamp pedal switch input to the control module.
System Power Mode: This parameter displays the position of the ignition switch.
Throttle Actuator Control Circuit Status: This parameter displays the state of the throttle actuator control circuits. The parameter displays Fault if the throttle actuator control circuit is open, shorted to ground, or shorted to voltage. This parameter displays indeterminate until the circuit is commanded ON.
TAC System Learned Counts: This parameter displays the steps counted in learning the throttle actuator control parameters. The last step learned is 11.
Torque Converter Clutch (TCC) Status: This parameter displays the commanded status of the torque convertor clutch.
Transmission Control Module (TCM) Requested Torque: This parameter displays the calculated amount torque requested by the controller.
Transmission Control Module (TCM) Torque Increase: This parameter displays if the controller has responsed the torque increase request.
Traction Control System (TCS) Torque Increase: This parameter displays if the controller has responsed the torque increase request.
Transmission Control Module (TCM) Torque Reduction Active: This parameter displays whether the transmission control module is reducing torque.
Traction Control System (TCS) Torque Reduction Active: This parameter displays whether EBTCM has determined a reduction in torque taking place.
Torque Delivered Signal: This is the calculated torque output from the engine to the transmission used by the EBTCM for the traction control system operation.
Torque Request Signal: The electronic brake traction control module (EBTCM) sends a Desired Torque Level signal request to the control module. This decreases torque from the powertrain in order to reduce wheel slip during acceleration for the traction control.
Total Fuel Trim Avg. Bank 1 or Bank 2: This parameter displays the overall fuel trim from the idle/decel cell and the cruise/accel cell.
Total Misfire Count: 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 Desired Angle: This parameter displays the desired TP angle commanded by the control module.
TP Indicated Angle: This parameter displays the percent of throttle opening as calculated by the control module using information from the 2 TP sensors.
TP Sensor 1: This parameter displays the actual voltage on the TP sensor 1 signal circuit as measured by the control module.
TP Sensor 1 Learned Minimum: This parameter displays the learned minimum value of throttle position (TP) sensor 1 as recorded by the control module during the last learn procedure.
TP Sensor 2: This parameter displays the actual voltage on the TP sensor 2 signal circuit as measured by the control module.
TP Sensor 2 Learned Minimum: This parameter displays the learned minimum value of throttle position sensor 2 as recorded by the control module during the last learn procedure.
TP Sensor 1 and 2: This parameter displays Disagree when the control module detects that TP sensor 1 voltage signal is not within the correct relationship to TP sensor 2. The scan tool displays Agree under normal operating conditions.
Traction Control Status: This parameter displays Active if the electronic brake and traction control module (EBTCM) is commanding traction control.
Vehicle Speed Sensor: 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).
Volumetric Efficiency: This parameter displays the calculated volumetric efficiency of the engine as calculated by the control module.
Warm-ups Since DTC Cleared: This parameter indicates the number of warm-up cycles that have occurred since DTCs were cleared. The scan tool will display a higher counts as more warm-up cycles have occurred since the DTCs were cleared.