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

A/C Relay Circuit Status: This parameter displays the diagnostic state of the output driver for the air conditioning (A/C) clutch relay control circuit. The scan tool will display OK or Fault. OK indicates that no circuit faults are detected during the current test. Fault indicates that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

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.

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 depressed to a high percentage when the accelerator pedal is fully depressed.

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 depressed to a high voltage when the accelerator pedal is fully depressed.

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 depressed to a high percentage when the accelerator pedal is fully depressed.

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 depressed to a high voltage when the accelerator pedal is fully depressed.

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 depressed to a high percentage when the accelerator pedal is fully depressed.

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.

Catalytic Converter Protection Active: This parameter indicates the status of the control module control for catalytic converter protection. The scan tool will indicate YES if the control module is adjusting fuel and ignition quantity and timing to protect the catalytic converter from damage. The scan tool will indicate NO if the control module is in a normal fuel and ignition control mode.

Commanded Gear: This parameter displays the transmission gear commanded by the control module. The scan tool will display P/N when the transmission is commanded to park or neutral. The scan tool will display R when the transmission is commanded to reverse. The scan tool will display 1-5 when the transmission is commanded into a specific low gear.

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.

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 to 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.

Current Gear Signal: This parameter displays the status of the current gear signal to the control module from the transmission. The scan tool will display Valid when the signal matches the commanded gear position from the control module. The scan tool will display Invalid when the signal does not match the commanded state of the transmission.

Cycles Of Misfire Data: This parameter displays the number of cylinder firing events that were recorded as misfires as determined by the control module. the scan tool will display a high value as misfire events increase. The scan tool will display a lower value when there are fewer misfire events.

Cylinder 1-8 IC 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 IC Circuit Status: This parameter displays the diagnostic state of the output driver for the ignition control circuit. 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 1-8 Injector Circuit Status: This parameter displays the current diagnostic state of the output driver for the injector control circuit. 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.

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 Exhaust CMP BN 1: This parameter displays the desired exhaust camshaft position for Bank 1, as determined by the control module. The scan tool will display a higher value for more advanced exhaust valve timing, such as at high load or speed conditions. The scan tool will display a lower value for a less advanced exhaust valve timing, such as at idle.

Desired Exhaust CMP BN 2: This parameter displays the desired exhaust camshaft position for Bank 2, as determined by the control module. The scan tool will display a higher value for more advanced exhaust valve timing, such as at high load or speed conditions. The scan tool will display a lower value for a less advanced exhaust valve timing, such as at idle.

Desired HO2S Bank 1 Sensor 1: This parameter indicates the desired heated oxygen sensor (HO2S) bank 1 sensor 1 output voltage as calculated by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value when the control module enriches the system, and a lower value during leaner running conditions.

Desired HO2S Bank 2 Sensor 1: This parameter indicates the desired heated oxygen sensor (HO2S) bank 2 sensor 1 output voltage as calculated by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value when the control module enriches the system, and a lower value during leaner running conditions.

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

Desired Ignition Spark: This parameter displays the desired ignition spark as determined by the control module. The scan tool will display a higher value when more spark is desired, such as heavy load conditions. The scan tool will display a lower value when less spark is desired, such as at idle.

Desired Intake CMP BN 1: This parameter displays the desired exhaust camshaft position for Bank 1, as determined by the control module. The scan tool will display a higher value for more advanced intake valve timing, such as at high load or speed conditions. The scan tool will display a lower value for a less advanced intake valve timing, such as at idle.

Desired Intake CMP BN 2: This parameter displays the desired intake camshaft position for Bank 2, as determined by the control module. The scan tool will display a higher value for more advanced intake valve timing, such as at high load or speed conditions. The scan tool will display a lower value for a less advanced intake valve timing, such as at idle.

Desired Torque: This parameter displays the desired torque as calculated by the control module. The scan tool will display a higher value when more torque is desired, such as under high load conditions. The scan tool will display a lower value when less torque is desired, such as at idle.

EC Ignition Relay Command: This parameter displays the commanded state of the EC ignition relay control circuit. The scan tool will display ON or OFF. ON indicates the EC ignition relay control circuit is being grounded by the control module, allowing voltage to the ignition system. OFF indicates the EC ignition relay is not being commanded on by the control module.

EC Ignition Relay Feedback Signal: This parameter displays the voltage signal sent to the control module from the engine control ignition relay. The scan tool will display battery voltage when the engine is running. The scan tool will display no voltage when the relay is OFF.

ECM Reset: This parameter displays the status of the control module this ignition cycle. The scan tool will display Yes when an internal control module reset has occurred this ignition cycle. The scan tool will display NO when no internal control module reset has occurred this ignition cycle.

ECT Sensor: This parameter displays the temperature of the engine coolant calculated by the control module, based on the input from the engine coolant temperature sensor. When the coolant temperature is low, the scan tool will display a low temperature. When the coolant temperature is high, the scan tool will display a high temperature.

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 Off EVAP Test Conditions Met: This parameter displays the status of the engine off EVAP test (EONV). The scan tool will display Yes if the conditions have been met to run the EONV diagnostic tests. The scan tool will display No if the conditions have not been met to run the EONV diagnostics.

Engine Off EVAP Test Ran Last Ignition Cycle: This parameter displays the status of the engine off EVAP test (EONV) as determined by the control module. The scan tool will display Yes when the EONV diagnostic test has run during the last ignition cycle. The scan tool will display No when the EONV diagnostic has not run during the last ignition cycle.

Engine Off Time: This parameter displays the time elapsed since the engine turned off. The scan tool will display the time in hours, minutes and seconds. The engine off time will reset to zero when the engine starts.

Engine Oil Level Switch: This parameter displays the status of the engine oil level switch as determined by the control module. The control module uses this information to turn on the low engine oil lamp if the engine oil level remains approximately 1 quart low for a sufficient amount of time. The scan tool will display Low when the engine oil level is low. The scan tool will display Ok when the engine oil level is correct.

Engine Oil Life Remaining: This parameter displays the amount engine oil life remaining before requiring an oil change based on calculations by the control module. The scan tool will display lower values as the engine oil life approaches 0 miles.

Engine Oil Pressure Sensor: This parameter displays the pressure of the engine oil as calculated by the control module using a signal from the engine oil pressure (EOP) sensor. The scan tool will display oil pressure when the engine is running. The engine oil pressure sensor has a range of values indicating a low value when the oil pressure is low to a high value when the oil pressure is high.

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. The scan tool will display the time in hours, minutes and seconds. The engine run time will reset to zero when the engine stops running.

Engine Speed: This parameter displays the speed of the crankshaft as determined by the control module using an input from the Crankshaft Position (CKP) Sensor. The scan tool will display a high value at high engine speeds and a low value at low engine speeds.

Engine Torque: This parameter displays the torque output of the engine as calculated by the control module based on various inputs.

EVAP Fault History: This parameter displays the result of the EVAP system diagnostic as determined by the control module. The scan tool will display various messages, depending on the result of the test.

EVAP Purge Solenoid Circuit Status: This parameter displays the diagnostic state of the output driver for the evaporative emission purge solenoid control circuit as determined by the control module. 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.

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 Abort Reason: This parameter displays the reason the EVAP test was aborted by the control module. The scan tool will display various messaged to indicate the reason the last test failed to complete.

EVAP Test Result: This parameter displays the result of the EVAP test performed by the control module. The scan tool will display various messaged to indicate the final result of the test.

EVAP Test State: This parameter displays the status of the EVAP test performed by the control module. The scan tool will display various messaged to indicate the current status of the test. The scan tool will display Wait For Purge, Test Running, or Test Complete.

EVAP Vent Solenoid Circuit Status: This parameter displays the diagnostic state of the output driver for the evaporative emission vent solenoid control circuit as determined by the control module. 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.

EVAP Vent Solenoid Command: This parameter displays the state of the evaporative emission (EVAP) vent solenoid commanded by the control module. The scan tool will display a venting when the control module is commanding the EVAP vent solenoid to be open . The scan tool will display a not venting when the control module is commanding the EVAP vent solenoid to be closed.

Exhaust CMP Angle Bank 1 or Bank 2: This parameter displays the degrees of advanced exhaust camshaft angle related to crankshaft position as determined by the control module based on input from the exhaust CMP sensors. The scan tool will display a higher value for a more advanced exhaust camshaft position. The scan tool will display a lower value when the exhaust camshaft is not being advance, such as at idle.

FC Relay 1 Circuit Status: This parameter displays the diagnostic state of the output driver for the cooling fan relay 1 control circuit. 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.

FC Relay 1 Command: This parameter displays the commanded state of the cooling fan relay 1 control circuit. The cooling fan relay 1 should be on when the scan tool indicates the FC Relay 1 Command is On. The cooling fan relay 1 should be off when the scan tool indicates the FC Relay 1 Command is Off.

FC Relay 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the cooling fan relay 2 control circuit. 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.

FC Relay 2 Command: This parameter displays the commanded state of the cooling fan relay 2 control circuit. The cooling fan relay 2 should be on when the scan tool indicates the FC Relay 2 Command is On. The cooling fan relay 2 should be off when the scan tool indicates the FC Relay 2 Command is Off.

Fuel Level Sensor Left Tank: This parameter displays the voltage from the sensor used to monitor the fuel level inside the left fuel tank. The scan tool will display a low voltage reading when that 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 Right Tank: This parameter displays the voltage from the sensor used to monitor the fuel level inside the right 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 Pump Relay Circuit Status: This parameter displays the diagnostic state of the output driver for the fuel pump relay control circuit. 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.

Fuel Pump Relay Command: This parameter displays the commanded state of the fuel pump relay control circuit. The fuel pump relay should be on when the scan tool indicates the Fuel Pump Relay Command is On. The fuel pump relay should be off when the scan tool indicates the Fuel Pump Relay Command is Off.

Fuel Pump Relay Signal: The scan tool displays Volts The amount of voltage the lift pump system is drawing. Also, a good functional check of the lift pump relay and oil pressure switch.

Fuel Tank Level Remaining: This parameter displays the amount of fuel remaining in the fuel tank as measured in liters or gallons. The control module determines the amount of fuel remaining in the tank by using information from the fuel level sensor(s). The scan tool will display a higher value with a full fuel tank, and a lower value with an empty 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: This parameter displays the rated maximum quantity of fuel the fuel tank will hold. This is calibrated in the control module to match the vehicle.

Fuel Trim Cell: This parameter displays the fuel trim cell number as calculated by the control module based on engine speed and load inputs. The scan tool will display a lower number as conditions are nearer to idle, and a higher value as conditions approach maximum engine speed and maximum load.

Fuel Trim Learn: This parameter indicated if the control module is being commanded to adjusting long term fuel trim in response to the short term fuel trim. The scan tool displays Enabled or Disabled. When fuel trim is being learned because of an external command, the scan tool displays Enabled. Under normal conditions the scan tool displays Disabled.

Fuel Volatility: This parameter indicates the rate the fuel can be vaporized in the cylinder as calculated by the control module. The scan tool will display HIGH when the fuel volatility is high. The scan tool will display LOW when the fuel volatility is low.

Generator L-Terminal Signal Command: This parameter indicates whether the control module is allowing the generator to operate. The control module can disable the generator under certain conditions. The scan tool will YES if the control module is allowing generator operation, while NO indicates that the control module is not allowing generator operation.

HO2S Bank 1 Sensor 1: This parameter indicates the heated oxygen sensor (HO2S) bank 1 sensor 1 output voltage as measured by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions.

HO2S Bank 1 Sensor 2: This parameter indicates the heated oxygen sensor (HO2S) bank 1 sensor 2 output voltage as measured by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions. The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control oxygen sensor s. This is due to the oxygen storage capacity of an efficiently operating catalyst.

HO2S Bank 2 Sensor 1: This parameter indicates the heated oxygen sensor (HO2S) bank 2 sensor 1 output voltage as measured by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions.

HO2S Bank 2 Sensor 2: This parameter indicates the heated oxygen sensor (HO2S) bank 2 sensor 2 output voltage as measured by the control module. The scan tool value fluctuates constantly while operating in Closed Loop. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions. The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control oxygen sensor s. This is due to the oxygen storage capacity of an efficiently operating catalyst.

HO2S Heater Bn 1 Sen. 1: This parameter displays the duty cycle of the HO2S Heater when commanded by the control module. HO2S Heater Bn 1 Sen. 1 is a range of values indicating a low percentage when the heater circuit is commanded ON less to a high percentage when the heater circuit is commanded ON more.

HO2S Heater Bn 1 Sen. 2: This parameter displays the duty cycle of the HO2S Heater when commanded by the control module. HO2S Heater Bn 1 Sen. 2 is a range of values indicating a low percentage when the heater circuit is commanded ON less to a high percentage when the heater circuit is commanded ON more.

HO2S Heater Bn 2 Sen. 1: This parameter displays the duty cycle of the HO2S Heater when commanded by the control module. HO2S Heater Bn 2 Sen. 1 is a range of values indicating a low percentage when the heater circuit is commanded ON less to a high percentage when the heater circuit is commanded ON more.

HO2S Heater Bn 2 Sen. 2: This parameter displays the duty cycle of the HO2S Heater when commanded by the control module. HO2S Heater Bn 2 Sen. 2 is a range of values indicating a low percentage when the heater circuit is commanded ON less to a high percentage when the heater circuit is commanded ON more.

Hot Open Loop: This parameter indicates the status of the fuel delivery system. The scan tool will display Active if the fuel system is running in open loop due to a temperature concern. The scan tool will display Inactive if the fuel system is operating normally.

IAT Sensor: This parameter displays the temperature of the air entering the engine as calculated by the control module based on the input from the intake air temperature sensor. The scan tool will display a low value when the air temperature is low, and a high value when the air temperature is high.

Ignition 0 Signal: This parameter displays the state of the ignition 0 input to the control module from the ignition switch. The scan tool will display On when the ignition switch is in the ignition 0 position. The scan tool will display Off when the ignition switch is in any other position.

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. The scan tool will display a low value when the voltage is low. The scan tool will display a high value, such as battery voltage, when the voltage is higher.

Ignition Spark Efficiency: This parameter indicates how much of the ignition capacity is being required to operate the engine as calculated by the control module. The scan tool will display a high value when more spark is require, such as high load conditions. The scan tool will display low values when less spark is required, such as at idle.

Initial Brake applied signal: This parameter indicates the status of the initial brake applied switch as determined by the control module. The scan tool will display applied when the brake pedal is depressed. The scan tool will display released when the brake pedal is not depressed.

Injector 1-8 Command: This parameter displays the commanded on time of each fuel injector by the control module. The scan tool will display a low value at idle, and a high value during high engine speeds and loads.

Injector PWM Bank 1 Average: This parameter indicates the average commanded ON time for each injector on Bank 1 by the control module. The scan tool will display a larger value for a longer injector commanded ON time, causing more fuel to be delivered to the cylinders. The scan tool will display a smaller value for a shorter injector commanded ON time, causing less fuel to be delivered to the cylinders.

Injector PWM Bank 2 Average: This parameter indicates the average commanded ON time for each injector on Bank 2 by the control module. The scan tool will display a larger value for a longer injector commanded ON time, causing more fuel to be delivered to the cylinders. The scan tool will display a smaller value for a shorter injector commanded ON time, causing less fuel to be delivered to the cylinders.

Instant FT Bank 1: This parameter indicates the instant fuel trim of Bank 1 as calculated by the control module. The scan tool will display a low value when little fuel is being required, and a higher value when more fuel is being required to maintain proper fuel trim.

Instant FT Bank 2: This parameter indicates the instant fuel trim of Bank 2 as calculated by the control module. The scan tool will display a low value when little fuel is being required, and a higher value when more fuel is being required to maintain proper fuel trim.

Intake CMP Angle Bank 1 or Bank 2: This parameter displays the degrees of advanced intake camshaft angle related to crankshaft position as determined by the control module based on input from the intake CMP sensors. The scan tool will display a higher value for a more advanced intake camshaft position. The scan tool will display a lower value when the intake camshaft is not being advance, such as at idle.

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 sensor(s). the scan tool displays a high value for a large amount of spark retard, and a low value for a small amount of spark retard.

Long Term FT Bank 1: This parameter is calculated by the control module based on the Short Term FT value. The Long Term FT bank 1 is used for the long term correction of the fuel delivery in bank 1. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

Long Term FT Bank 2: This parameter is calculated by the control module based on the Short Term FT value. The Long Term FT bank 2 is used for the long term correction of the fuel delivery in bank 1. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

LT FT Bank 1 High RPM/Load: This parameter is calculated by the control module based on the Short Term FT value under High RPM/Load conditions. The Long Term FT bank 1 is used for the long term correction of the fuel delivery in bank 1. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

LT FT Bank 2 High RPM/Load: This parameter is calculated by the control module based on the Short Term FT value under High RPM/Load conditions. The Long Term FT bank 2 is used for the long term correction of the fuel delivery in bank 2. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

LT FT Bank 1 low RPM/Load: This parameter is calculated by the control module based on the Short Term FT value under low RPM/Load conditions. The Long Term FT bank 1 is used for the long term correction of the fuel delivery in bank 1. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

LT FT Bank 2 low RPM/Load: This parameter is calculated by the control module based on the Short Term FT value under low RPM/Load conditions. The Long Term FT bank 2 is used for the long term correction of the fuel delivery in bank 2. The scan tool will a high value for a large amount of long term fuel correction, and 0% for no long term fuel trim correction. The scan tool will display a negative value when fuel system is running too rich and fuel is being removed from the combustion event. The scan tool will display a positive value if the fuel system is running lean and fuel is being added to the combustion event.

Loop Status: This parameter indicates the status of the fuel delivery by the control module. The scan tool will display Closed Loop if the control module is controlling the fuel delivery according to the heated oxygen sensor (HO2S ) voltages. The scan tool will display Open Loop if the control module controls fuel delivery based on throttle position, coolant temperature, and air flow inputs only. The vehicle will run in open loop until all of the conditions are met to allow Closed Loop operation.

MAF Sensor: This parameter indicates the quantity calculated by the control module based on a signal from the Mass Airflow (MAF) Sensor. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.

MAF Sensor: This parameter indicates the frequency signal received from the mass airflow (MAF) sensor by the control module. The scan tool will display a high value at high engine speeds, and a low value at low engine speeds.

MAP Sensor: This parameter indicates the manifold absolute pressure inside the engine as calculated by the control module based on the signal from the manifold absolute pressure (MAP) sensor. The scan tool will display a higher value wide open throttle, and a lower value at idle.

MIL Circuit Status: This parameter displays the diagnostic state of the output driver for the malfunction indicator lamp control circuit. 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.

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.

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 accumulated since an emission diagnostic trouble code was cleared. The scan tool will display increasing mileage as the vehicle is driven.

Misfire Detects Rough Road: This Parameter indicates the status of rough road detection during a misfire condition. The scan tool will display YES when the control module has received rough road information from another module during a misfire event. The scan tool will display NO when the control module has detected a misfire, and there is no rough road indication from another controller.

Misfire History Cyl. #1: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 1 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #2: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 2 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #3: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 3 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #4: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 4 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #5: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 5 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #6: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 6 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #7: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 7 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Misfire History Cyl. #8: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on Cylinder 8 as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter. This counter should display some activity, but the activity should be the same for all cylinders.

Moderate Brake Apply Signal: This parameter indicates the status of the moderate brake applied switch as determined by the control module. The scan tool will display applied when the brake pedal is depressed. The scan tool will display released when the brake pedal is not depressed.

PNP Switch: This parameter indicates the range selection of the automatic transmission as calculated by the control module based on input from the PNP switch. The scan tool will display, In Gear, Park, or Neutral depending on the PNP switch position.

Power Enrichment: This parameter indicates if the control module has detected conditions appropriate to operate in Power Enrichment mode. The scan tool will display Active if the mode is in operation, and Inactive if the mode is not in operation. The control module enters Open Loop operation and increases injector pulse width when in power enrichment mode.

Powertrain Induced Chassis Pitch Command: This parameter indicates if the control module has detected conditions that would induce the chassis to pitch. The scan tool will display Active if the mode is in operation, and Inactive if the mode is not in operation.

Reduced Engine Power: This parameter indicates if the control module has detected that a throttle actuator control (TAC) system fault has occurred. The scan tool will display Active if the mode is in operation, and Inactive if the mode is not in operation. The control module limits engine power when this mode is Active.

Reference Voltage 1 Signal: This parameter displays the voltage on the reference 1 circuit as measured by the control module. The scan tool will display a higher value when the voltage is higher. the scan tool will display a lower value when the voltage is lower.

Reference Voltage 2 Signal: This parameter displays the voltage on the reference 2 circuit as measured by the control module. The scan tool will display a higher value when the voltage is higher. the scan tool will display a lower value when the voltage is lower.

Short Term FT Bank 1: This parameter displays the short term correction to fuel delivery for bank 1 by the control module in response to the amount of time the oxygen sensor voltage spends above or below the 450 mV threshold. The scan tool will display 0% if no adjustments are required. the scan tool will display a higher positive value if fuel has to be added, and a higher negative value if fuel has to be removed.

Short Term FT Bank 2: This parameter displays the short term correction to fuel delivery for bank 2 by the control module in response to the amount of time the oxygen sensor voltage spends above or below the 450 mV threshold. The scan tool will display 0% if no adjustments are required. the scan tool will display a higher positive value if fuel has to be added, and a higher negative value if fuel has to be removed.

Spark: This parameter displays the spark timing being commanded by the control module on the IC circuit. The scan tool will display a negative value if the spark timing is before top dead center (BTDC) or spark advance; the scan tool will display a positive value if the spark timing is after top dead center (ATDC) or spark retard. Because the ignition control module sets spark advance at a fixed value BTDC while operating in bypass mode, the displayed spark advance only reflects true spark timing when the PCM has commanded IC mode.

Start Up ECT: This parameter Indicates the engine coolant temperature at engine start up as calculated by the control module based on the signal from the ECT sensor. the scan tool will display a higher value on a warmer engine, and a lower value on a colder engine.

Start Up IAT: This parameter Indicates the intake air temperature at engine start up as calculated by the control module based on the signal from the IAT sensor. the scan tool will display a higher value during warmer underhood temperatures, , and a lower value during colder underhood temperatures.

Starter Relay Circuit Status: This parameter displays the diagnostic state of the output driver for the starter enable relay control circuit. 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.

Starter Relay Command: This parameter displays the commanded state of the starter relay control circuit. The starter relay should be on when the scan tool indicates the Starter Relay Command is On. The starter relay should be off when the scan tool indicates the Starter Relay Command is Off.

Stoplamp Pedal Switch: This parameter displays the state of the brake pedal as determined by the stoplamp pedal switch. This switch turns on the stoplamp when the brake pedal is depressed. The scan tool will display Applied when the brake pedal is depressed, and Released when the brake pedal is not depressed.

TAC Motor Command: This parameter indicates the required duty cycle to maintain a desired throttle position. The scan tool will display a higher value if more effort is required to move the throttle to the desired position, such as physical resistance. The scan tool will display a lower value if less effort is required to move the throttle to the desired position.

TAC Direction: This parameter displays the commanded direction of the throttle blade by the TAC system. The scan tool will display CLOSED when the throttle is being commanded to the closed position. The scan tool will display OPEN when the throttle is commanded to an OPEN position.

TCS Control Signal: This parameter indicates the status of the traction control system affecting the power of the engine. the scan tool will display REDUCED when the traction control system is commanding reduced power by the control module. The scan tool will display NONE when the TCS is not commanding reduced engine power.

Torque Delivered Signal: This parameter indicates the torque delivered from the engine to the transmission as calculated by the control module. The scan tool will display a higher value for higher torque, and a lower value for lower torque.

Torque Request Signal: This parameter indicates the torque requested from the engine to the transmission as calculated by the control module. The scan tool will display a higher value for higher torque, and a lower value for lower torque.

Total Misfire Counter: This parameter displays the number of possible misfires during the last 200 cylinder firing events detected on all cylinders as calculated by the control module. The misfires are calculated based on engine crankshaft rotation speed variations. The scan tool displays an incrementing counter.

TP Desired Angle: This parameter indicates the desired throttle angle calculated by the throttle actuator control (TAC) module as commanded by the vehicle operator. the scan tool will display a higher value when the accelerator pedal is depressed, and a lower value as the accelerator pedal is released.

TP Indicated Angle: This parameter displays the angle of the throttle plate as calculated by the control module using the signals from the throttle position sensor(s). The TP indicated angle is a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is wide open.

TP Learned: This parameter indicates the status of the throttle position learn system. If the system learns the throttle position, the scan tool will display YES. The scan tool will display NO if the throttle position is not learned by the control module.

TP Learn Enable: This parameter indicates the status of the throttle position learn system. If the system is in the mode to learn the throttle position, the scan tool will display YES. The scan tool will display NO if the throttle position is not being learned by the control module.

TP Learn Required: This parameter indicates the status of the throttle position learn system. If the system has not learned the throttle position, the scan tool will display YES. The scan tool will display NO if the throttle position is already learned or the system is currently learning throttle position.

TP Sensor 1: This parameter displays the voltage signal sent to the control module from throttle position (TP) sensor 1 of the throttle assembly. TP sensor 1 is a range of values indicating a low voltage when the throttle is closed to a high voltage when the throttle plate is fully open.

TP Sensor 1: This parameter displays the angle of the throttle position (TP) sensor 1 as calculated by the control module using the signal from the TP sensor 1. TP sensor 1 is a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is fully open.

TP Sensor 1 Learned Min.: This parameter displays the learned minimum voltage for TP sensor 1 as determined by the control module this ignition cycle.

TP Sensor 2 Learned Min.: This parameter displays the learned minimum voltage for TP sensor 2 as determined by the control module this ignition cycle.

TP Sensor 2: This parameter displays the voltage signal sent to the control module from throttle position (TP) sensor 2 of the throttle assembly. TP sensor 2 is a range of values indicating a high voltage when the throttle is closed to a low voltage when the throttle plate is fully open.

TP Sensor 2: This parameter displays the angle of the throttle position (TP) sensor 2 as calculated by the control module using the signal from the TP sensor 2. TP sensor 2 is a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is fully open.

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

Transmission Gear Selector Signal: This parameter displays the status of the transmission gear selector signal to the control module from the transmission. The scan tool will display Valid when the signal matches the commanded gear position from the control module. The scan tool will display Invalid when the signal does not match the commanded state of the transmission.

TWC Temperature Calculated: This parameter indicates the temperature of the catalytic converter as calculated by the control module based on various system inputs. The scan tool will display a higher value at higher catalytic converter temperatures. the scan tool will display lower values at lower catalytic converter temperatures.

Vehicle Security Status: This parameter displays the current status of the fuel disabling security system. The scan tool will display Fuel Continue when the security system allows fuel delivery. The scan tool will display Fuel Disable when the security system disables the fuel delivery.

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

VTD Password Learn Enabled: This parameter indicates the status of the control vehicle password learn system. If the system learns the security password, the scan tool will display YES. The scan tool will display NO if the theft deterrent password is not learned by all modules.