Part 1

Scan Tool Data Definitions

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 Volts Reference 1
- This parameter displays the voltage sensed on the 5-volt reference 1 circuit at the control module. The scan tool will display a higher value at higher voltage. The scan tool will display a lower value at lower voltage.

5 Volts Reference 1 Circuit Status
- This parameter will display OK if the circuit is good or Fault if a short to ground, short to B+ or open circuit is present.

5 Volts Reference 2
- This parameter displays the voltage sensed on the 5-volt reference 2 circuit at the control module. The scan tool will display a higher value at higher voltage. The scan tool will display a lower value at lower voltage.

5 Volts Reference 2 Circuit Status
- This parameter will display OK if the circuit is good or Fault if a short to ground, short to B+ or open circuit is present.

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.

Air Flow Calculated
- This parameter displays the air flow of the engine as calculated by the control module using information from the manifold absolute pressure (MAP) sensor. The scan tool will display a range of values indicating a high air flow when MAP pressure is high and a low air flow when MAP pressure is low. This value is listed in grams per second (g/s).

AIR Indicated Pressure
- This parameter displays the Secondary Air Injection (AIR) system pressure above barometric pressure as calculated based on a signal sent to the control module from the sensor used to monitor the pressure inside the AIR injection system. The scan tool will display a low value when the pressure in the AIR system pressure is low. The scan tool will display a high value when the pressure in the AIR system is high.

AIR Pressure Sensor
- This parameter displays the voltage signal sent to the control module from the sensor used to monitor the pressure inside the AIR injection system. The scan tool will display a low voltage when the pressure in the AIR system is high. The scan tool will display a high voltage when the pressure in the AIR system is low.

AIR Pressure Sensor
- This parameter displays the actual AIR system pressure as calculated based on a signal sent to the control module from the sensor used to monitor the pressure inside the AIR injection system. The scan tool will display a low value when the pressure in the AIR system is low. The scan tool will display a high value when the pressure in the AIR system is high.

AIR Pressure Sensor Variance
- This parameter displays the difference between the desired AIR pressure calculated by the control module and the actual AIR pressure. The scan tool will display a higher value if the difference is large, and a lower value if the difference is small.

AIR Pump Relay Circuit Status
- This parameter displays the status of the output driver for the AIR pump relay control circuit. The scan tool will display OK, Indeterminate, Short B+, Short Gnd, or Open. OK indicates that no circuit faults are detected during the current test. The different faults will indicates that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

AIR Pump Relay Command
- This parameter displays the commanded state of the AIR pump relay control circuit. The scan tool will display ON or OFF. ON indicates the AIR pump relay control circuit is being grounded by the control module, allowing voltage to the AIR pump. OFF indicates the AIR pump relay is not being commanded on by the control module.

AIR Solenoid Circuit Status
- This parameter displays the status of the output driver for the AIR solenoid control circuit. The scan tool will display OK, Incomplete, Short B+, Short Gnd, or Open. OK indicates that no circuit faults are detected during the current test. The different faults will indicates that a short or open circuit/component exists, electronically disconnecting the circuit/component from the control module.

AIR Solenoid Command
- This parameter displays the commanded state of the AIR solenoid control circuit. The scan tool will display ON or OFF. ON indicates the AIR solenoid control circuit is being grounded by the control module, opening the AIR solenoid and allowing vacuum to the shutoff or combination valve(s). OFF indicates the AIR solenoid is not being commanded on by the control module.

Ambient Air Temperature
- Outside temperature at any given altitude expressed in degrees.

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 accelerator pedal position (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 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 listed in counts.

APP Sensor 1
- This parameter displays the voltage signal sent to the control module from 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 Indicated Position
- This parameter displays the angle of the 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 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 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 Indicated Position
- This parameter displays the angle of the 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 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 Signal
- This parameter displays the state of the brake pedal position switch 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.

BPP Circuit Signal
- The BCM uses the Brake Pedal Position sensor as an indication that the brake pedal is applied or released.

Calc. TWP Temp
- Calculated catalytic converter 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 incrementing 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 resynchronize the CKP sensor.

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

CMP Active Counter
- This parameter displays an incrementing counter when the control module receives a signal from the camshaft position (CMP) sensor.

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

Cold Startup
- This parameter displays whether the engine meets the conditions for a cold startup during the present ignition cycle. The scan tool displays Yes when the conditions for a cold startup are met during this ignition cycle. The scan tool displays No when the conditions for a cold startup are not met during the present ignition cycle. Conditions for a cold startup require the coolant temperature and the intake air temperature to be below a predetermined temperature and within a certain range of each other. These conditions must occur after the engine was warmed up to a specific temperature during the previous ignition cycle.

Commanded A/F Equivalence Ratio
- Equivalence numbers greater than one represent excess fuel in the fuel air mix. Equivalence numbers less than one represent a deficiency of fuel in the fuel air mix for complete combustion. The equivalence ratio will be reported as one when the vehicle is in Closed Loop.

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.

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 IC Circuit Status
- This parameter displays the status of the output driver for the ignition control circuits. The scan tool will display OK, Incomplete, Short B+, Short Gnd/Open. The scan tool will display OK if the circuit is operating correctly. The scan tool will display a 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 EGR Position
- This parameter displays the position of the exhaust gas recirculation (EGR) valve commanded by the control module. The scan tool will display 0 percent when the control module is commanding the EGR valve closed. The scan tool will display a higher percentage when the EGR valve is commanded open.

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.

Distance Since DTC Cleared
- This parameter displays the distance accumulated since an emission diagnostic trouble code was cleared. The scan tool will display increasing distance as the vehicle is driven.

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 EC ignition relay control circuit is being grounded by the control module, allowing voltage to other control module circuits and systems. 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.

ECT Sensor
- This parameter displays the temperature of the engine coolant based on the input from the engine coolant temperature (ECT) 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.

EGR Learned Minimum Position
- This parameter displays the learned minimum position of the EGR valve as calculated by the control module. The scan tool will display a low value if the current closed EGR position is the same as the last ignition cycle. The scan tool will display a higher value if the EGR valve has closed at a new position.

EGR Flow Test Count
- This parameter indicates the number of EGR flow test samples collected during the current ignition cycle.

EGR Position Sensor
- This parameter displays the voltage signal received from the EGR valve position sensor by the control module. The scan tool will display a lower value when the EGR valve is closed, and a higher value when the EGR valve is open.

EGR Position Sensor
- This parameter displays EGR valve position as calculated by the control module based on an input from the EGR valve position sensor. The scan tool will display a lower value when the EGR valve is closed, and a higher value when the EGR valve is open.

EGR Position Variance
- This parameter displays the difference between the desired EGR valve position calculated by the control module and the actual EGR position input from the EGR valve position sensor. The scan tool will display a higher value if the difference is large, and a lower value if the difference is small.

EGR Solenoid Circuit Status
- This parameter displays the status of the output driver for the EGR solenoid 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.

EGR Solenoid Command
- This parameter displays the duty cycle commanded by the control module for the EGR valve. The scan tool will display a high percentage when the EGR valve is commanded open. The scan tool will display a low percentage when the EGR valve is commanded closed.

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 Time
- This parameter displays the time elapsed since the engine was shut OFF.

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 Switch
- This parameter displays the state of the EOP as determined by the control module. The control module monitors the EOP switch to determine if the EOP is sufficient. The scan tool will display low when the EOP is below a predetermined value.

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 CKP sensor. The scan tool will display a high value at high engine speeds and a low value at low engine speeds.

EVAP Fault History
- This parameter displays the result of the evaporative emission (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 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 the appropriate fault if there is an open, short to ground or a short to voltage on the circuit. The scan tool will display Incomplete if the diagnostic has not completed.

EVAP Vent Solenoid Command
- This parameter displays the state of the 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 a not venting when the control module is commanding the EVAP vent solenoid to be closed.

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 the appropriate fault if there is an open, short to ground or a short to voltage on the circuit. The scan tool will display Incomplete if the diagnostic has not completed.

Ext. Travel BPP Signal
- This parameter will display the state of the brake pedal, applied or released.

Fuel Level Sensor
- This parameter displays the voltage from the sensor used to monitor the fuel level inside the 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 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 the appropriate fault if there is an open, short to ground or a short to voltage on the circuit.

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 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 displays Low, Moderate, or High. The scan tool will display HIGH when the fuel volatility is high. The scan tool will display LOW when the fuel volatility is low.