GM Service Manual Online
For 1990-2009 cars only

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.

4WD Signal: This parameter displays the state of the transfer case based on the signal from the front axle indicator switch. The scan tool will display Enabled or Disabled. Enabled indicates the front axle is locked in four wheel drive and the front axle indicator switch is closed, supplying voltage to the controller on the axle switch signal circuit. Disabled indicates the transfer case is not in four wheel drive and the front axle indicator switch is open.

4WD Low Signal: This parameter displays the state of the transfer case based on the signal from the four wheel drive (4WD) low switch. The scan tool will display Enabled or Disabled. Enabled indicates the transfer case is in 4WD low gear and the 4WD low switch is closed, completing the low signal circuit. Disabled indicates the transfer case is not in 4WD low gear and the 4WD low switch is open.

A/C Relay Command: This parameter displays the commanded state of the air conditioning (A/C) clutch relay control circuit. The scan tool will display ON or OFF. ON indicates the A/C clutch relay control circuit is being grounded by the control module, allowing voltage to the A/C compressor clutch. OFF indicates the A/C clutch relay is not being commanded on by the control module.

A/C Request Signal: This parameter displays the state of the air conditioning (A/C) request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls. The scan tool will display Yes or No. Yes indicates the control module is receiving a request from the HVAC system to ground the A/C clutch relay control circuit, engaging the A/C compressor clutch. No indicates the control module is not receiving a request from the HVAC system to ground the A/C clutch relay control circuit.

APP Average: This parameter displays the average of the 3 accelerator pedal position (APP) sensors as calculated by the throttle actuator control (TAC) module. The APP average is a range of values indicating a low number when the accelerator pedal is not pressed to a high number when the accelerator pedal is fully pressed. This value is listed in counts.

APP Indicated Angle: This parameter displays the angle of the accelerator pedal as calculated by the control module using the signals from the accelerator pedal position sensors. The APP indicated angle is a range of values indicating a low percentage when the accelerator pedal is not pressed to a high percentage when the accelerator pedal is fully pressed.

APP Sensor 1: This parameter displays the voltage signal sent to the control module from accelerator pedal position (APP) sensor 1 of the APP sensor assembly. APP sensor 1 is a range of values indicating a low voltage when the accelerator pedal is not pressed to a high voltage when the accelerator pedal is fully pressed.

APP Sensor 1: This parameter displays the angle of the accelerator pedal position (APP) sensor 1 as calculated by the control module using the signal from the APP sensor 1. APP sensor 1 is a range of values indicating a low percentage when the accelerator pedal is not pressed to a high percentage when the accelerator pedal is fully pressed.

APP Sensor 1 and 2: This parameter displays the results of a control module test that compares the signals from the accelerator pedal position (APP) sensors 1 and 2 . The scan tool will display Agree or Disagree. Agree indicates that APP sensor 1 and APP sensor 2 voltages correspond to the same accelerator pedal position. Disagree indicates that APP sensor 1 and APP sensor 2 voltages correspond to different accelerator pedal positions.

APP Sensor 2: This parameter displays the voltage signal sent to the control module from accelerator pedal position (APP) sensor 2 of the APP sensor assembly. APP sensor 2 is a range of values indicating a low voltage when the accelerator pedal is not pressed to a high voltage when the accelerator pedal is fully pressed.

APP Sensor 2: This parameter displays the angle of the accelerator pedal position (APP) sensor 2 as calculated by the control module using the signal from the APP sensor 2. APP sensor 2 is a range of values indicating a low percentage when the accelerator pedal is not pressed to a high percentage when the accelerator pedal is fully pressed.

BARO : This parameter displays the barometric pressure as calculated by the control module using the signal from the manifold absolute pressure (MAP) sensor measured when the ignition is turned on with the engine not running. The control module will update the barometric pressure during wide-open throttle (WOT) conditions.

Clutch Pedal Switch: This parameter displays the current state of the clutch pedal as determined by the control module.

CMP Sensor - High To Low: This parameter displays the number of times the signal voltage from the camshaft position (CMP) sensor changes from high to low. The scan tool will display these transitions as counts.

CMP Sensor - Low To High: This parameter displays the number of times the signal voltage from the camshaft position (CMP) sensor changes from low to high. The scan tool will display these transitions as counts.

Coolant Level Switch: This parameter displays the level of engine coolant as determined by the control module. The control module determines the level of the coolant using the signal from a switch used to monitor the engine coolant level. The scan tool will display low when the engine coolant level is low. The scan tool will display OK when the coolant level is correct.

Cruise Control Active: This parameter displays the status of the cruise control system as determined by the control module. The scan tool will display Yes when the cruise control system is in control of vehicle speed. The scan tool will display No when the cruise control system is not operating.

Cruise Disengage 1-8 History: The scan tool indicates the last 8 cruise control disengages in order, from 1 to 8. There are 20 possible causes for the cruise control to disengage.

Cruise Inhibit Signal Command: This parameter displays the commanded state of the cruise inhibit signal circuit. The scan tool will display On when the control module is inhibiting cruise control operation. The scan tool will display OFF when the control module is allowing cruise control operation.

Cruise On/Off Switch: This parameter displays the state of the On/Off switch input to the control module . The scan tool will display ON when the cruise switch is ON.

Cruise Release Brake Pedal Switch: This parameter displays the state of the Cruise Release Brake Pedal Switch as determined by the control module. The scan tool will display Released or Applied. Released indicates the brake pedal is not being pushed down , allowing the cruise control to be enabled. Applied indicates the brake switch is being applied, disabling cruise control operation.

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.

Current Gear: This parameter displays the transmission gear commanded by the control module. The scan tool will display 1 when the control module has commanded first gear regardless of the gear selector position. The scan tool will display up to 6 depending upon which gear is commanded and what transmission is in the vehicle. The scan tool will display 9 if the transmission gear is not known.

Cycles Of Misfire Data: This parameter displays the number of cylinder firing events that were recorded as misfires as determined by the control module.

Decel. Fuel Cutoff: This parameter displays the status of the operating mode used to turn OFF the fuel injectors during certain deceleration conditions. When the scan tool displays Active, the control module has turned OFF the fuel injectors. When the scan tool displays Inactive, the fuel system is operating normally.

Desired IAC Airflow: This parameter displays the desired airflow in the idle air control (IAC) passage as calculated by the control module.

Desired Idle Speed: This parameter displays the engine idle speed in RPM commanded by the control module. The control module compensates for various engine loads in order to maintain the desired engine RPM at idle. This parameter is not valid unless the engine is running.

DTC Set This Ignition: This parameter displays if a diagnostic trouble code (DTC) set during the current ignition cycle. The scan tool will display YES if a DTC is stored this ignition cycle.

ECT Sensor: This parameter displays the temperature of the engine coolant based on a voltage input from the engine coolant temperature (ECT) sensor to the control module. The scan tool will display a low value when coolant temperature is low, and a high value when the coolant temperature is high.

Engine Load: This parameter displays the engine load in percent based on inputs to the control module from various engine sensors. The scan tool will display a low percentage when the engine is at idle with little or no load. The scan tool will display a high percentage when the engine is running at a high RPM under a heavy load.

Engine Oil Level Switch: This parameter displays the state of the engine oil level switch as determined by the control module. The scan tool will display OK or Low. OK indicates that the engine oil level is not too low for safe operation of the engine. Low indicates the engine oil level is abnormally low and has closed the engine oil level switch.

Engine Oil Life Remaining: This parameter displays the amount of engine oil life remaining before requiring an oil change. This number is calculated by the control module based on many inputs and is displayed as a percent. The lower the percentage, the sooner the next oil change will be required.

Engine Run Time: This parameter displays the time elapsed since the engine was started. The scan tool will display the time in hours, minutes and seconds. The engine run time will reset to zero as soon as the engine stops running.

Engine Speed: This parameter displays the speed of the crankshaft as calculated by the control module based on inputs from the crankshaft position (CKP) sensor. The scan tool will display the engine speed in revolutions per minute (RPM).

EVAP Purge Solenoid Command: This parameter displays the on-time or duty cycle of the evaporative emission (EVAP) purge solenoid commanded by the control module expressed as a percent. The scan tool will display a high percentage when the control module is commanding the EVAP purge solenoid to be open a large amount . The scan tool will display a low percentage when the control module is commanding the EVAP purge solenoid to be open a small amount. The scan tool will display 0 when the control module is commanding the EVAP purge solenoid closed.

EVAP Test Result: The scan tool displays No Result, Passed, Aborted, Fail-DTC P0440, Fail-DTC P0442, Fail-DTC P0446, or Fail-DTC P1441. The scan tool displays PASS if the control module determines that the EVAP test has passed.

EVAP Test State: The scan tool displays Waiting For Purge, Test Running, or Test Completed. This parameter indicates the state of the EVAP service bay test.

EVAP Vent Solenoid Command: This parameter displays the commanded state of the EVAP vent solenoid control circuit . The scan tool will display Venting or Not Venting. Venting indicates the EVAP vent solenoid is not being commanded on by the control module. Not Venting indicates the EVAP vent solenoid is being commanded ON by the control module.

Fail Counter: The scan tool displays the number of times that a diagnostic has failed.

Fuel Alcohol Content: This parameter displays the percentage of alcohol in the fuel. This value is calculated by the control module using HO2S signals. The scan tool will display a low percentage when there is very little alcohol in the fuel. The scan tool will display a high percentage when the alcohol content of the fuel is high.

Fuel Level Sensor: This parameter displays the voltage from the signal produced by the sensor used to monitor the fuel level inside the fuel tank. The scan tool will display a low voltage reading when the fuel level in the tank is low or near empty. The scan tool will display a high voltage reading when the fuel level in the tank is high or near full.

Fuel Level Sensor Rear Tank: This parameter displays the voltage from the signal produced by the sensor used to monitor the fuel level inside the rear fuel tank. The scan tool will display a low voltage reading when the fuel level in the rear tank is low or near empty. The scan tool will display a high voltage reading when the fuel level in the tank is high or near full.

Fuel Tank Level Remaining: This parameter displays the amount of fuel remaining in all fuel tanks of the vehicle as measured in liters or gallons. The control module calculates the amount of fuel remaining in the tank by using information from the fuel level sensors.

Fuel Tank Level Remaining: This parameter displays the amount of fuel remaining in tall of the fuel tanks of the vehicle as a percentage. The control module calculates this level using the signals from the sensors used to monitor the fuel level in the fuel tanks. The scan tool will display a low reading when the total fuel level in the vehicle is low or near empty. The scan tool will display a high reading when the fuel level in the tank is high or near full.

Fuel Tank Pressure Sensor: This parameter indicates the pressure or vacuum in the fuel tanks as determined by the control module based on inputs from the fuel tank pressure sensor. The scan tool displays in mm/Hg or in H2O. The scan tool indicates a negative value if there is a vacuum in the fuel tank, and a positive value if there is pressure in the fuel tank.

Fuel Tank Pressure Sensor: This parameter displays the voltage signal sent to the control module from the sensor used to monitor the pressure inside the fuel tank. The scan tool will display a low voltage when the pressure in the fuel tank is high. The scan tool will display a high voltage when the pressure in the fuel tank is low or in a vacuum.

Fuel Tank Rated Capacity: The scan tool displays liters or gallons. This parameter displays the fuel tank capacity as determined by the calibrations of the vehicle.

Fuel Temperature: This parameter displays the current fuel temperature as calculated by the control module based on input from the fuel composition sensor. The scan tool will display a higher value at higher fuel temperatures. The scan tool will display a lower value at lower fuel temperatures.

Fuel Trim Cell: This parameter displays the fuel trim cell as calculated by the control module based on many sensor inputs. 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. If the scan tool displays Disabled, then long term fuel trim will not respond to changes in short term fuel trim.

Generator F-Terminal Signal : This parameter displays the commanded state of the generator by the control module. A high value indicates a high charging command, and a low value indicates a low charging command.

Generator L-Terminal Signal Command: This parameter displays if the control module is allowing the generator to operate. The scan tool displays ON if the generator is allowed to operate. The scan tool displays OFF if the control module is disabling the generator.

HO2S Bank 1 Sensor 1: This parameter displays the voltage from the signal produced by the heated oxygen sensor used to monitor fuel trim for cylinder bank 1. The scan tool will display a low voltage reading when that cylinder bank is running lean. The scan tool will display a high voltage reading when that cylinder bank is running rich.

HO2S Bank 1 Sensor 2: This parameter displays the voltage from the signal produced by the heated oxygen sensor used to monitor catalyst efficiency for cylinder bank 1. The scan tool will display a low voltage reading when that cylinder bank is running lean. The scan tool will display a high voltage reading when that cylinder bank is running rich.

HO2S Bank 2 Sensor 1: This parameter displays the voltage from the signal produced by the heated oxygen sensor used to monitor fuel trim for cylinder bank 2. The scan tool will display a low voltage reading when that cylinder bank is running lean. The scan tool will display a high voltage reading when that cylinder bank is running rich.

HO2S Bank 2 Sensor 2: This parameter displays the voltage from the signal produced by the heated oxygen sensor used to catalyst efficiency for cylinder bank 2. The scan tool will display a low voltage reading when that cylinder bank is running lean. The scan tool will display a high voltage reading when that cylinder bank is running rich.

HO2S Heater Bank 1 Sensor 1: This parameter displays the current through the control module when the bank 1 sensor 1 HO2S heater is commanded ON by the control module. HO2S Heater Bank 1 Sensor 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bank 1 Sensor 2: This parameter displays the current through the control module when the bank 1 sensor 2 HO2S heater is commanded ON by the control module. HO2S Heater Bank 1 Sensor 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bank 2 Sensor 1: This parameter displays the current through the control module when the bank 2 sensor 1 HO2S heater is commanded ON by the control module. HO2S Heater Bank 2 Sensor 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Heater Bank 2 Sensor 2: This parameter displays the current through the control module when the bank 2 sensor 2 HO2S heater is commanded ON by the control module. HO2S Heater Bank 2 Sensor 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

IAT Sensor: This parameter displays the temperature of the intake air calculated by the control module based on the input from the intake air temperature (IAT). The scan tool will display a low value for a low intake air temperature, and a high value for a high intake air temperature.

Ignition 1 Signal: 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.

Injector PWM Bank 1 Average: The scan tool displays milliseconds. This parameter is the average time the control module turns on each fuel injector on that bank. The scan tool will display a higher value with a longer pulse width, or a lower value with a shorter pulse width.

Injector PWM Bank 2 Average: The scan tool displays milliseconds. This parameter is the average time the control module turns on each fuel injector on that bank. The scan tool will display a higher value with a longer pulse width, or a lower value with a shorter pulse width.

Knock Retard: The scan tool displays in degrees. This parameter indicates the amount of timing retard commanded by the control module. The scan tool will display a lower value if no knock is detected, and a higher value as more knock is detected and the control module retards the ignition timing.

Long Term FT Avg. Bn1: The scan tool displays %. This parameter is the average long term fuel trim for this bank as calculated by the control module. The scan tool will display a value of more than 0 percent indicating that time is being added to the injector pulse width, increasing the amount of fuel to this bank of the engine. The scan tool will display a value of less than 0 indicating time is being subtracted from the injector pulse width, reducing the amount of fuel to this bank of the engine. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Long Term FT Avg. Bn2: The scan tool displays %. This parameter is the average long term fuel trim for this bank as calculated by the control module. The scan tool will display a value of more than 0 percent indicating that time is being added to the injector pulse width, increasing the amount of fuel to this bank of the engine. The scan tool will display a value of less than 0 indicating time is being subtracted from the injector pulse width, reducing the amount of fuel to this bank of the engine. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Long Term FT Bank 1: The scan tool displays %. This parameter is the long term fuel trim for this bank as calculated by the control module. The scan tool will display a value of more than 0 percent indicating that time is being added to the injector pulse width, increasing the amount of fuel to this bank of the engine. The scan tool will display a value of less than 0 indicating time is being subtracted from the injector pulse width, reducing the amount of fuel to this bank of the engine. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Long Term FT Bank 2: The scan tool displays %. This parameter is the long term fuel trim for this bank as calculated by the control module. The scan tool will display a value of more than 0 percent indicating that time is being added to the injector pulse width, increasing the amount of fuel to this bank of the engine. The scan tool will display a value of less than 0 indicating time is being subtracted from the injector pulse width, reducing the amount of fuel to this bank of the engine. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Loop Status: The scan tool displays Open or Closed. The scan tool displays Closed Loop if the control module is controlling the fuel delivery according to the heated oxygen sensor (HO2S) voltages. The scan tool displays open loop if the control module is not adjusting for HO2S inputs. In open loop the control module bases fuel deliver on throttle position, engine coolant temperature, and mass airflow sensor inputs.

Low Oil Lamp Command: This parameter displays the commanded state of the low oil lamp control circuit by the control module. The scan tool will display ON if the lamp is commanded ON by the control module. The scan tool will display OFF if the lamp is not being commanded by the control module.

MAF Sensor: The scan tool displays g/s. This parameter indicates the airflow into the engine as calculated by the control module based on mass airflow (MAF) sensor inputs. The scan tool will display a high value at higher engine speeds, and a low value at idle.

MAF Sensor: The scan tool displays in Hz. This parameter indicates the frequency signal sent from the MAF sensor to the control module. the scan tool will display a high value indicates a higher engine speed. The scan tool will display a low value at idle.

MAP Sensor: The scan tool displays kPa. This parameter displays the pressure inside of the intake manifold as calculated by the control module based on the input from the MAP sensor. The scan tool will display a high value at wide open throttle (WOT). The scan tool will display a low value at idle speed.

MAP Sensor: This parameter displays the voltage signal from the MAP sensor to the control module. The scan tool will display a high value at wide open throttle (WOT). The scan tool will display a low value at idle speed.

MIL Command: This parameter displays the commanded state of the malfunction indicator lamp (MIL) control circuit. The malfunction indicator lamp should be ON when the scan tool indicates the MIL Command is ON. The malfunction indicator lamp should be OFF when the scan tool indicates the MIL Command is OFF. The control module will command the MIL ON when the ignition is ON with the engine OFF in order to perform a bulb check.

Mileage Since DTC Cleared: The scan tool displays km or miles. This parameter indicates the mileage accumulated since an emission diagnostic trouble code cleared.

Mileage Since First Failure: The scan tool will display in km or miles. This parameter indicates the difference in mileage between when the DTC first set and the current vehicle mileage as calculated by the control module.

Mileage Since Last Failure: The scan tool will display in km or miles. This parameter indicates the difference in mileage between when the DTC last set and the current vehicle mileage as calculated by the control module.

Misfire Counter Status:  The misfire counter shows the relative number of failed misfire tests since the misfire DTC P0300 became active.

Misfire Current Cyl. #1 - #8: The scan tool will display in counts. This parameter indicates the number of cylinder firing events detected as possible misfires on each cylinder during the last 200 crankshaft revolutions as calculated by the control module. The scan tool will display a low number for a low number of cylinder misfire events. The scan tool will display a high number for a high number of cylinder misfire events.

Misfire History Cyl. #1 - #8: The scan tool displays in counts. This parameter displays the total level of cylinder misfires that have been calculated for each cylinder by the control module. This parameter will not update or show activity until a misfire DTC has become active. The misfire history counters will update every 200 cylinder firing events.

Not Run Counter:  The scan tool displays the number of times a DTC diagnostic has not reached the predetermined criteria in order to run since the first DTC run failure.

Pass Counter:  The scan tool displays the number of times a DTC has run and passed.

PCM Reset: The scan tool displays Yes or No. This parameter indicates when the internal PCM resets. The scan tool displays YES when an internal PCM reset occurred. The scan tool displays NO under the normal operating conditions.

PCM/VCM in VTD Fail Enable: The scan tool displays Yes or No. The scan tool displays Yes if the body control module (BCM) and the control module lose communications with each other after the BCM sends the correct password. The scan tool displays No if the BCM is communicating the correct password to the PCM.

Power Enrichment: Scan tool displays ACTIVE or INACTIVE. ACTIVE displayed indicates that the control module has detected conditions appropriate to operate in Power Enrichment mode. The control module commands Power Enrichment mode when a large increase in throttle position and load is detected. While in Power Enrichment, the control module will increase the amount of fuel delivered by entering Open Loop and increasing the injector pulse width.

Reduced Engine Power: The scan tool displays Active or Inactive. The scan tool displays Active when the control module receives a signal from the TAC module that a throttle actuator control system fault is occurring. The scan tool displays inactive when the engine is operating normally.

Short Term FT Avg. Bn1:  The scan tool displays %. This parameter indicates the average short term fuel trim for this bank. The scan tool will display a value more than 0 if the time is being added to the injector pulse width, increasing the amount of fuel to that bank of the engine to compensate for a lean condition sensed by the oxygen sensors on that bank. The scan tool will display a value less than 0 if time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine to compensate for a rich condition sensed by the oxygen sensors on that bank. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Short Term FT Avg. Bn2:  The scan tool displays %. This parameter indicates the average short term fuel trim for this bank. The scan tool will display a value more than 0 if the time is being added to the injector pulse width, increasing the amount of fuel to that bank of the engine to compensate for a lean condition sensed by the oxygen sensors on that bank. The scan tool will display a value less than 0 if time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine to compensate for a rich condition sensed by the oxygen sensors on that bank. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Short Term FT Bank 1:  The scan tool displays %. This parameter indicates the current short term fuel trim for this bank. The scan tool will display a value more than 0 if the time is being added to the injector pulse width, increasing the amount of fuel to that bank of the engine to compensate for a lean condition sensed by the oxygen sensors on that bank. The scan tool will display a value less than 0 if time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine to compensate for a rich condition sensed by the oxygen sensors on that bank. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Short Term FT Bank 2:  The scan tool displays %. This parameter indicates the current short term fuel trim for this bank. The scan tool will display a value more than 0 if the time is being added to the injector pulse width, increasing the amount of fuel to that bank of the engine to compensate for a lean condition sensed by the oxygen sensors on that bank. The scan tool will display a value less than 0 if time is being subtracted from the injector pulse width, reducing the amount of fuel to the engine to compensate for a rich condition sensed by the oxygen sensors on that bank. A value of 0 percent indicates no compensation is required to operate the engine at the desired air/fuel ratio.

Spark: This parameter is the desired spark advance calculated by the control module based on many sensor inputs. The scan tool will display a lower value at idle speed, and a higher value under heavy acceleration and load conditions.

Start Up ECT: This parameter indicates the engine coolant temperature at startup, as calculated by the control module based on the input from the engine coolant temperature sensor. The scan tool will display a higher value at higher engine startup temperatures, and a lower value at lower startup temperatures.

Stop Lamp Pedal Switch: This parameter displays the state of the brake pedal as determined by the control module based on an input from the stop lamp pedal switch. This switch turns ON the stop lamps when the brake pedal is pressed. The scan tool will display Applied when the brake pedal is pressed.

TAC/PCM Communication Signal: This parameter indicates the status of the communication between the TAC module and the control module. The scan tool will display OK if the circuits are operating normally. The scan tool will display Fault if there is an interrupt in the communication.

TCC Enable Solenoid Command: This parameter displays the commanded state of the torque converter clutch (TCC) solenoid control circuit. The scan tool will display ON or OFF. ON indicates the TCC solenoid control circuit is being grounded by the control module, operating the torque converter. OFF indicates the TCC solenoid is not being commanded ON by the control module.

TCC PWM Solenoid Command: This parameter indicates the commanded state of the TCC PWM Solenoid by the control module. The scan tool displays ON or OFF. The scan tool displays ON when the commanded state of the solenoid is ON. The scan tool displays OFF when the solenoid is OFF.

TFP Switch: The scan tool displays Park/Neutral, Reverse, Drive, or Invalid. This display indicates the decoded status of the two A/B inputs from the automatic transmission fluid pressure manual valve position switch.

Torque Delivered Signal: The scan tool displays ft-lbs or N·m. This parameter represents the pulse width modulation (PWM) signal which indicates the percent of available torque the engine is delivering to the drive wheels. The electronic brake/traction control module (EBCM) monitors the Traction Control Torque signal to ensure that the powertrain control module (PCM) is responding properly to the Traction Control Desired Torque signal.

Torque Request Signal: The scan tool displays ft-lbs or N·m. Represents the pulse width modulation (PWM) signal from the electronic brake and traction control module. The electronic brake/traction control module (EBCM) reduces the traction control desired torque signal pulse width when a drive wheel slippage situation is detected. The powertrain control module (PCM) monitors the traction control desired torque signal and reduces drive wheel slippage as necessary by retarding spark timing, decreasing boost solenoid PWM, or increasing air/fuel ratio. The PCM can also turn OFF up to three fuel injectors if the traction control desired torque signal indicates a large enough amount of drive wheel slippage.

TP Desired Angle: This parameter indicates the TP angle commanded by the control module. The scan tool will display a low value at idle, and a high value at wide open throttle (WOT).

TP Indicated Angle: This parameter displays the angle of the throttle position (TP) in percent. This information is calculated by the control module using the signals from the throttle position sensors. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

TP Sensor 1: This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plates. This parameter is for sensor 1 of the throttle position (TP) sensor assembly. The scan tool will display a low voltage when the throttle plates are at rest. The scan tool will display a high voltage when the throttle plates are fully open.

TP Sensor 1: This parameter displays the angle of the throttle position (TP) sensor 1 in percent. This information is calculated by the control module using the signal from the throttle position sensor 1. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

TP Sensor 2: This parameter displays the voltage signal sent to the control module from the sensor used to monitor the position of the throttle plates. This parameter is for sensor 2 of the throttle position (TP) sensor assembly. The scan tool will display a high voltage when the throttle plates are at rest. The scan tool will display a low voltage when the throttle plates are fully open.

TP Sensor 2: This parameter displays the angle of the throttle position (TP) sensor 2 in percent. This information is calculated by the control module using the signal from the throttle position sensor 2. The scan tool will display a low percentage when the throttle plates are closed. The scan tool will display a high percentage when the throttle plates are fully open.

TP Sensors 1 and 2: This parameter displays the results of a control module test that compares signals from the throttle position (TP) sensors 1 and 2 . The scan tool will display Agree when the signal from TP sensor 1 corresponds with the signal from TP sensor 2. The scan tool will display Disagree when the signal from TP sensor 1 conflicts with the signal from TP sensor 2.

TR Switch: This parameter indicates the current state of the gear select switch on the transmission/transaxle as calculated by the control module based on the TR switch. The scan tool status will switch from High to Low as different combinations are met. On the scan tool in Park, the PRNDL would read P and A will be Low, and B and C will be High.

Traction Control Signal: This parameter displays the current status of the traction control system. The scan tool will display ACTIVE if the traction control system is operating. The scan tool will display INACTIVE if the traction control system is not requested because of a wheel slippage condition.

Vehicle Speed Sensor: This parameter indicates the vehicle speed calculated by the control module based on an input from the vehicle speed sensor (VSS). The scan tool will display a high value at higher vehicle speeds, and a low value at lower vehicle speeds.

VTD Auto Learn Timer: The scan tool displays Active/Inactive. This parameter indicates if the control module is ready to learn the theft deterrent password. The scan tool will display active if the system is ready to learn. The scan tool will display inactive if the system has timed out or is not ready to learn the password.

VTD Fuel Disable: This parameter Indicates if the VTD module has received proper information to enable or disable fuel. The scan tool will display Active or Inactive. The scan tool will display Active if the control module does not receive the correct password from the BCM. The scan tool will display Inactive if the control module receives the correct password from the BCM. If the system is Active, the engine will not start.

VTD Fuel Disable Until Ignition Off: The scan tool displays Yes or No. With the ignition ON and a VTD code present, the scan tool displays Yes.

Warm-ups w/o Emission Faults: The scan tool displays in counts. This parameter counts the number of warm up cycles without an emission fault present. The parameter increments until a fault occurs. If a fault occurs, the counter reverts to 0 until the fault is corrected. Clearing information with a scan tool or a loss of power to the PCM also resets the counter to 0.

Warm-ups w/o Non-Emission Faults: The scan tool displays in counts. This parameter counts the number of warm up cycles without a non-emission fault present. The parameter increments until a fault occurs. If a fault occurs, the counter reverts to 0 until the fault is corrected. Clearing information with a scan tool or a loss of power to the PCM also resets the counter to 0.