GM Service Manual Online
For 1990-2009 cars only

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

5-Volt Reference 1: This parameter displays the voltage that the control module 5-volt reference 1 circuit senses. The scan tool will display a high value, when the voltage is higher. The scan tool will display a low value, when the voltage is lower.

5-Volt Reference 2: This parameter displays the voltage that the control module 5-volt reference 2 circuit senses. The scan tool will display a high value, when the voltage is higher. The scan tool will display a low value, when the voltage is lower.

5-Volt Reference 1 or 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the 5-volt reference 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.

Ambient Air Temperature: This parameter displays the temperature of the ambient air as calculated by the control module based on the input from the ambient 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.

APP Indicated Angle: This parameter displays the angle of the accelerator pedal position (APP) as calculated by the control module based on the signals from the APP 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: This parameter displays the average of the 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 depressed to a high number when the accelerator pedal is fully depressed. This value is displayed by number.

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 voltage when the accelerator pedal is not depressed to a high voltage 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 Indicated Sensor 2: This parameter displays the angle of the accelerator pedal position 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 (Gasoline): 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.

BPP Circuit Signal: This parameter displays the circuit status of the brake pedal position (BPP) as determined by the brake pedal circuit. The scan tool will display Applied when the brake pedal is depressed, and Released when the brake pedal is not depressed.

BPP Signal: This parameter displays the switch status of the brake pedal position (BPP) as determined by the brake pedal switch. The scan tool will display Applied when the brake pedal is depressed, and Released when the brake pedal is not depressed.

Calculated Engine Oil Temperature: 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.

Calculated TWC Temperature Bank 1 or Bank 2: This parameter displays the temperature of the three-way converter (TWC) by the control module based on various sensor and drive inputs. The scan tool will display a high value at higher temperature, and a low value at low temperature.

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

CKP Active Counter: This parameter displays an incremental counter when the control module receives a signal from the crankshaft position (CKP) sensor.

CKP Resync Counter: This parameter displays the number of times the control module has to re-syncs with the CKP sensor.

CKP Sensor: This parameter displays the engine speed as calculated by the control module using the signal from the CKP sensor.

Commanded Air/Fuel and Equivalent Ratio: This parameter displays the air fuel ratio 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.

CMP Sensor: This parameter displays the engine speed as calculated by the control module using the signal from the CMP sensor. The scan tool will display a high value as engine speed is increased. The scan tool will display a low value as engine speed is decreased.

Cold Start-up: This parameter displays whether the engine meets the conditions for cold start-up during the current ignition cycle. The scan tool displays Yes, when the engine meets the conditions for cold start-up during the current ignition cycle. The scan tool displays No, when the engine doesn't meet the conditions for cold start-up during the current ignition cycle. The conditions for a cold start-up require the coolant temperature and the intake air temperature to be below a predetermined temperature and within a certain range of each other. The engine warm-ups the given temperature in the last ignition cycle, these conditions must exist.

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 Signal: This parameter displays 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.

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.

Cylinder 1-8 Knock Retard: This parameter displays the amount of knock retard commanded by the control module. The scan tool will display a lower value for more advanced timing, and a higher value for more retarded timing.

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 Bank 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 Bank 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 displays the desired HO2S bank 1 sensor 1 value as determined by the control module.

Desired HO2S Bank 2 Sensor 1: This parameter displays the desired HO2S bank 2 sensor 1 value as determined by the control module.

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 Intake CMP Bank 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 Bank 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.

EC Ignition Relay Circuit Status: This parameter displays the status of the output driver for the engine control (EC) ignition 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.

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 engine control ignition relay control circuit is being grounded by the control module, allowing voltage to the ignition system. OFF indicates the engine control 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.

ECT Sensor: This parameter displays the temperature of the engine coolant 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 Misfire 1-8 Fuel Injector Disabled: This parameter displays the state of the fuel injector driver controlled by the control module. The scan tool displays Yes, if detected fuel injector disabled due to engine misfire. The scan tool displays No, if detected fuel injector disabled by control module not due to engine misfire.

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 Running 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 running 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 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 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 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: This parameter displays the state of the evaporative emission (EVAP) vent solenoid commanded by the control module. The scan tool will display Venting when the control module is commanding the EVAP vent solenoid to be open. The scan tool will display 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 degree 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.

Exhaust CMP Bank 1 or Bank 2 Active Counter: This parameter displays an incremental counter when the control module receives a signal from the exhaust crankshaft position (CMP) sensor.

Exhaust CMP Bank 1 or Bank 2 Command: This parameter indicates the amount of camshaft advance commanded by the control module. The scan tool displays a high value for a large amount of advance; and a low value for a small amount of advance.

Exhaust CMP Bank 1 or Bank 2 Variance: This parameter indicates the variance between the actual camshaft angle and the commanded camshaft angle as determined by the control module. The scan tool will display a high value for large variances, or a low value if there is only a small variance.

Exhaust CMP Solenoid Bank 1 or Bank 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the exhaust CMP solenoid control circuit. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd, OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit component from the control module.

Extended Travel BPP Signal: This parameter displays the state of the extended travel brake pedal as determined from the extended travel brake pedal switch position. The scan tool will display Applied when the brake pedal is depressed greater than approximately 40 percent of the total travel.

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 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 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 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 Tank Level Remaining: his 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 Pressure Sensor: This parameter displays the fuel tank pressure as calculated based on a signal sent to the control module from the fuel tank pressure (FTP) sensor. The scan tool will display a low value when the pressure in the fuel tank is low or a vacuum. The scan tool will display a high value when the pressure in the fuel tank is high.

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 adjusting long term fuel trim in response to the short term fuel trim. The scan tool displays Enabled or Disabled. When conditions are appropriate for enabling long term fuel trim corrections, the scan tool displays Enabled.

Fuel Trim System Test State: This parameter indicates the status of the Fuel Trim System Test. The scan tool will display Disabled, Enabled, Monitoring, or Run Purge Test.

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.

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 sensors. 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 sensors. This is due to the oxygen storage capacity of an efficiently operating catalyst.

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, and indicating a high current when the heater circuit resistance is low.

HO2S Heater Bank 1 Sensor 1 Command: This parameter displays the state of the Bank 1 Sensor 1 heater commanded by the control module. The scan tool will display a high value when the heater command is increased, and a low value when the heater is not commanded On.

HO2S Heater Bank 1 Sensor 1 Command: This parameter displays the state of the Bank 1 Sensor 1 heater commanded by the control module. The scan tool will display ON when the heater is commanded On. The scan tool will display OFF when the heater is commanded Off.

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, and indicating 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, and indicating 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, and indicating a high current when the heater circuit resistance is low.

HO2S Heater Bank 1 Sensor 2 Command: This parameter displays the state of the Bank 1 Sensor 2 heater commanded by the control module. The scan tool will display a high value when the heater command is increased, and a low value when the heater is not commanded On.

HO2S Heater Bank 1 Sensor 2 Command: This parameter displays the state of the Bank 1 Sensor 2 heater commanded by the control module. The scan tool will display ON when the heater is commanded On. The scan tool will display OFF when the heater is commanded Off.

HO2S Heater Bank 2 Sensor 1 Command: This parameter displays the state of the Bank 2 Sensor 1 heater commanded by the control module. The scan tool will display a high value when the heater command is increased, and a low value when the heater is not commanded On.

HO2S Heater Bank 2 Sensor 1 Command: This parameter displays the state of the Bank 2 Sensor 1 heater commanded by the control module. The scan tool will display ON when the heater is commanded On. The scan tool will display OFF when the heater is commanded Off.

HO2S Heater Bank 2 Sensor 2 Command: This parameter displays the state of the Bank 2 Sensor 2 heater commanded by the control module. The scan tool will display a high value when the heater command is increased, and a low value when the heater is not commanded On.

HO2S Heater Bank 2 Sensor 2 Command: This parameter displays the state of the Bank 2 Sensor 2 heater commanded by the control module. The scan tool will display ON when the heater is commanded On. The scan tool will display OFF when the heater is commanded Off.

HO2S Heater Bank 1 Sensor 1 Circuit Status: This parameter displays the diagnostic state of the output driver for the HO2S heater bank 1 sensor 1. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd. OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

HO2S Heater Bank 1 Sensor 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the HO2S heater bank 1 sensor 2. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd. OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

HO2S Heater Bank 2 Sensor 1 Circuit Status: This parameter displays the diagnostic state of the output driver for the HO2S heater bank 2 sensor 1. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd. OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

HO2S Heater Bank 2 Sensor 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the HO2S heater bank 2 sensor 2. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd. OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

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.

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

Ignition Off Time: This parameter displays the time elapsed since the ignition was turned Off last time. The scan tool will display the time in hours, minutes and seconds.

Ignition Spark 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 when the voltage is high.

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. A shorter injector commanded ON time, causing less fuel to be delivered to the cylinders. The scan tool will display low value.

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. A shorter injector commanded ON time, causing less fuel to be delivered to the cylinders. The scan tool will display low value.

Injector 1-8 Disabled Due to Misfire: 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.

Intake CMP Bank 1 or Bank 2 Active Counter: This parameter displays an incremental counter when the control module receives a signal from the intake crankshaft position (CMP) sensor.

Intake CMP Bank 1 or Bank 2 Command: This parameter indicates the amount of the camshaft advance commanded by the control module. The scan tool displays a high value for a large amount of advance; and a low value for a small amount of advance.

Intake CMP Bank 1 or Bank 2 Variance: This parameter indicates the variance between the actual camshaft angle and the commanded camshaft angle as determined by the control module. The scan tool will display a high value for large Variances, or a low value if there is only a small Variance.

Intake CMP Solenoid Bank 1 or Bank 2 Circuit Status: This parameter displays the diagnostic state of the output driver for the intake CMP solenoid control circuit. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd, OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit component from the control module.

Intake Manifold Pressure: This parameter is the calculated difference between the manifold absolute pressure (MAP) and the supercharge inlet pressure (SCIP).

Knock Detected Cyl. 1-8: This parameter displays the status of each cylinder for knock detection by the control module. The scan tool will display YES if a knock condition has been detected related to that cylinder combustion event. The scan tool will display NO if no knock condition has been detected related to that cylinder combustion event.

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. 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 Avg--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 display a high value for a large amount of long term fuel correction, and 0 percent 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 Test Avg--Bank 1 or Bank 2: This parameter is calculated by the control module based on an intrusive test by the control module. The Long Term FT Test average used for the long term correction of the fuel delivery in each bank. The scan tool will display a high value for a large amount of long term fuel correction, and 0 percent 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 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 display a high value for a large amount of long term fuel correction, and 0 percent 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 display a high value for a large amount of long term fuel correction, and 0 percent 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 Performance Test: This parameter displays the status of the mass air flow (MAF) performance test controlled by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the tests.

MAF Sensor: This parameter indicates the quantity calculated by the control module based on a signal from the mass air flow (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 air flow (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 Performance Test 1: This parameter displays the status of the manifold absolute pressure (MAP) performance test 1 controlled by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the tests.

MAP Performance Test 2: This parameter displays the status of the manifold absolute pressure (MAP) performance test 2 controlled by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the tests.

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 on as a result of a type A or B DTC. The scan tool will display NO if the MIL is illuminated for another reason, such as transmission DTCs.

Misfire Current Cyl. 1-8: This parameter displays the number of possible misfires during the last 200 cylinder firing events 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. 1-8: This parameter displays the number of possible misfires that have occurred after 195 current misfires have been counted on cylinder 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.

Output Speed Sensor: his parameter displays the rotational speed of the transmission output shaft. The scan tool displays output shaft speed as revolutions per minute (RPM).

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.

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.

SCB Solenoid Circuit Status: This parameter displays the diagnostic state of the output driver for the supercharger bypass (SCB) solenoid control circuit. The scan tool will display OK, Incomplete, Open, Short B+, or Short Gnd. OK indicates that no circuit faults are detected during the current test. Incomplete indicates the circuit test is not complete. The other displays indicate that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

SBC Solenoid Command: This parameter displays the commanded state of the supercharger bypass (SCB) solenoid control circuit. The scan tool will display a duty cycle percentage. A low value indicates the solenoid is not being commanded on, resulting in higher increase pressure. A high value indicates the solenoid is being commanded On, resulting in lower boost pressure because the bypass valve is venting around the supercharger.

SCIP: This parameter indicates the pressure at the supercharger inlet as calculated by the control module based on the signal from the supercharger inlet pressure sensor. The scan tool will display a higher value wide open throttle, and a lower value at idle.

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

SCIP Sensor: This parameter shows the voltage signal received by the control module from the SCIP sensor. The scan tool displays a low voltage at idle, and a high voltage at wide open throttle. Barometric pressure and altitude can effect these values.

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 percent 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 percent 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.

Throttle Actuator Forced Engine Shut Down: This parameter indicates the status of throttle actuator control (TAC) control by the control module. The scan tool will display YES if the engine has been off due to a throttle control fault and display NO if the engine has not been off by a throttle control fault.

TAC Motor: This parameter indicates the status of throttle actuator control (TAC) motor by the engine control module (ECM). The scan tool will display Enabled if TAC motor operation is allowed. The scan tool will Display disabled if the TAC motor is disabled.

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.

TCS Torque Delivered Signal: This parameter indicates the percent of torque output from the engine to the transmission as calculated by the control module. The scan tool will display a high value at high torque, and a low value at low torque.

TCS Torque Request Signal: This parameter indicates the percent of torque requested from the engine to the transmission as calculated by the control module. The scan tool will display a high value at high torque, and a low value at low torque.

Torque Delivered Signal: This is the calculated torque output from the engine to the transmission used by the electronic brake traction control Module (EBTCM) for the traction control system operation.

Torque Management Spark Retard: This parameter indicates torque at which the ignition spark timing is being retarded by the control module. The scan tool will display a high value under extreme torque control conditions such as rotating wheels. The scan tool will display a low value under low torque control conditions such as light driving.

Total Knock Retard: This parameter indicates ignition spark timing is being retarded due to all control systems monitored by the control module. The scan tool will display a high value during extreme conditions such as high temperatures and antilock braking. The scan tool will display a low value under light load.

Total Misfire Count: This parameter displays the number of possible misfires during the last 200 cylinder firing events 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 (TP) 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 Performance Test: This parameter displays the status of the throttle position (TP) performance test controlled by the control module. The scan tool will display OK if no fault is found. The scan tool will display Fault if the control module detects a fault during the tests.

TP Sensor 1: This parameter displays the voltage signal sent to the control module from throttle position sensor 1 of the throttle assembly. The 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 Indicated Position: This parameter displays the angle of the throttle plate sensor 1 as calculated by the control module using the signals from the throttle position sensor 1. The TP Sensor 1 has a range of values indicating a low percentage when the throttle is closed to a high percentage when the throttle is wide open.

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

TP Sensor 2: This parameter displays the voltage signal sent to the control module from throttle position sensor 2 of the throttle assembly. The TP sensor 2 has 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 Indicated Position: This parameter displays the angle of the throttle plate sensor 2 as calculated by the control module using the signals from the throttle position.

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

TP Sensors 1 and 2: This parameter displays the results of a control module test that compares the signals from the 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.

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 high value at high vehicle speed, and a low value at low vehicle speed.

Warm-up 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 number the more warm up cycles that have occurred since DTCs were cleared.

Warm-up w/o Emission Faults: This parameter indicates the number of warm up cycles that have occurred without an emission fault. The scan tool will display 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without a non-emission fault.

Warm-up w/o Non-Emission Faults: This parameter indicates the number of warm up cycles that have occurred without an non-emission fault. The scan tool will display 0 if a fault has occurred. The scan tool will display a higher count if a number of warm up cycles have occurred without an non-emission fault.

Wide Open Throttle: This parameter indicates the throttle status commanded by the control module. The scan tool will display YES if the vehicle throttle is commanded to wide open. The scan tool will display NO if the vehicle throttle is commanded to an amount less than 100 percent.