Scan Tool Data Definitions Part 1
SCAN TOOL DATA DEFINITIONS 1The Engine Scan Tool Data Definitions contain a brief description of all engine related parameters available on the scan tool. The list is in alphabetical order. A given parameter may appear in any one of the data lists. In some cases, the parameter may appear more than once or in more than one data list in order to group certain related parameters together.
A/C Clutch Feedback Signal: This parameter displays the state of the air conditioning (A/C) compressor clutch based on the signal from the switched side of the A/C clutch relay. The scan tool will display Relay On or Relay Off. Relay On indicates the A/C clutch relay has closed, allowing voltage to the A/C compressor clutch. Relay Off indicates the A/C clutch relay is open and the A/C compressor clutch is not engaged.
A/C High Side Pressure Sensor: This parameter displays the voltage signal sent to the control module from the A/C high side pressure sensor. The A/C high side pressure sensor has a range of values indicating a low refrigerant pressure when the voltage is low to a high refrigerant pressure when the voltage is high.
A/C High Side Pressure Sensor: This parameter displays the high side pressure of the air conditioning (A/C) system as calculated by the control module based on a signal from the A/C high side pressure sensor. The A/C high pressure sensor has a range of values indicating a low refrigerant pressure when the pressure is low to a high refrigerant pressure when the pressure is high. This value is listed in kPa.
A/C Relay Command: This parameter displays the commanded state of the air conditioning (A/C) clutch relay control circuit. The scan tool will display ON or OFF. ON indicates the A/C clutch relay control circuit is being grounded by the control module, allowing voltage to the A/C compressor clutch. OFF indicates the A/C clutch relay is not being commanded on by the control module.
A/C Request Signal: This parameter displays the state of the air conditioning (A/C) request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls. The scan tool will display Yes or No. Yes indicates the control module is receiving a request from the HVAC system to ground the A/C clutch relay control circuit, engaging the A/C compressor clutch. No indicates the control module is not receiving a request from the HVAC system to ground the A/C clutch relay control circuit.
Air Fuel Ratio: This parameter displays the ratio of air to fuel as calculated by the control module based on various sensor inputs. The scan tool will display a lower air fuel ratio when a richer air to fuel mixture is commanded. The scan tool will display a higher air fuel ratio when a leaner air to fuel mixture is commanded. In closed loop operation the air fuel ratio should normally be around 14.2-14.7 to 1.
APP Average: This parameter displays the average of the 3 accelerator pedal position (APP) sensors as calculated by the throttle actuator control (TAC) module. The APP average is a range of values indicating a low number when the accelerator pedal is not depressed to a high number when the accelerator pedal is fully depressed. This value is listed in counts.
APP Indicated Angle: This parameter displays the angle of the accelerator pedal as calculated by the control module using the signals from the accelerator pedal position sensors. The APP indicated angle is a range of values indicating a low percentage when the accelerator pedal is not 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 1 and 3: This parameter displays the results of a control module test that compares the signals from the accelerator pedal position (APP) sensors 1 and 3 . The scan tool will display Agree or Disagree. Agree indicates that APP sensor 1 and APP sensor 3 voltages correspond to the same accelerator pedal position. Disagree indicates that APP sensor 1 and APP sensor 3 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.
APP Sensor 2 and 3: This parameter displays the results of a control module test that compares the signals from the accelerator pedal position (APP) sensors 2 and 3 . The scan tool will display Agree or Disagree. Agree indicates that APP sensor 2 and APP sensor 3 voltages correspond to the same accelerator pedal position. Disagree indicates that APP sensor 2 and APP sensor 3 voltages correspond to different accelerator pedal positions.
APP Sensor 3: This parameter displays the voltage signal sent to the control module from accelerator pedal position (APP) sensor 3 of the APP sensor assembly. APP sensor 3 is a range of values indicating a high voltage when the accelerator pedal is not depressed to a low voltage when the accelerator pedal is fully depressed.
APP Sensor 3: This parameter displays the angle of the accelerator pedal position (APP) sensor 3 as calculated by the control module using the signal from the APP sensor 3. APP sensor 3 is a range of values indicating a high percentage when the accelerator pedal is not depressed to a low 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.
Clutch Pedal Switch: This parameter displays the current state of the clutch pedal as determined by the control module.
CMP Sensor - High To Low: This parameter displays the number of times the signal voltage from the camshaft position (CMP) sensor changes from high to low.
CMP Sensor - Low To High: This parameter displays the number of times the signal voltage from the camshaft position (CMP) sensor changes from low to high. The scan tool will display these transitions as counts.
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.
Column Lock Fuel Disable - ABS DTC: This parameter displays the status of fuel disabling due to an antilock brake system (ABS) diagnostic trouble code (DTC). Fuel is disabled after the engine is running for 5 seconds. The scan tool will display Yes if fuel is disabled because of a ABS DTC.
Column Lock Fuel Disable - BCM DTC: This parameter displays the status of fuel disabling due to a body control module (BCM) diagnostic trouble code (DTC). Fuel is disabled if the vehicle is in motion. The scan tool will display Yes if fuel is disabled because of a BCM DTC.
Column Lock - PCM-BCM Communication: This parameter displays the status of the security system that disables fuel due to a communications problem between modules. The engine will start and idle. Fuel is disabled when the vehicle is in motion.
Cruise Control Active: This parameter displays the status of the cruise control system as determined by the control module. The scan tool will display Yes when the cruise control system is in control of vehicle speed. The scan tool will display No when the cruise control system is not operating.
Cruise Disengage 1-8 History: This parameter displays the last 8 cruise control disengages in order from 1 to 8. The control module will disengage the cruise control for up to 20 different conditions.
Cruise On/Off Switch: This parameter displays the state of the on/off switch input to the control module . The scan tool will display On when the cruise switch is on.
Cruise Resume/Accel Switch: This parameter displays the state of the Resume/Accel switch input to the control module When the cruise control switch is in the on position and the Resume/Accel switch is activated, the scan tool displays On. When the Resume/Accel switch is released the scan tool displays Off.
Cruise Set/Coast Switch: This parameter displays the state of the Set/Coast switch input to the control module from the cruise control system. When the cruise control switch is in the on position and the Set/Coast switch is activated, the scan tool displays On. When the Set/Coast switch is released the scan tool displays Off.
Current Gear: This parameter displays the transmission gear commanded by the control module. The scan tool will display 1 when the control module has commanded first gear regardless of the gear selector position. The scan tool will display up to 6 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.
Cycles Of Misfire Data: This parameter displays the number of cylinder firing events that were recorded as misfires as determined by the control module.
Decel. Fuel Cutoff: This parameter displays the status of the operating mode used to turn off the fuel injectors during certain deceleration conditions. When the scan tool displays Active, the control module has turned off the fuel injectors. When the scan tool displays Inactive, the fuel system is operating normally.
Desired Idle Speed: This parameter displays the engine idle speed in RPM commanded by the control module. The control module compensates for various engine loads in order to maintain the desired engine RPM at idle. This parameter is not valid unless the engine is running.
DTC Set This Ignition: This parameter displays if a diagnostic trouble code (DTC) set during the current ignition cycle.
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 Oil Level Switch: This parameter displays the level of engine oil as determined by the control module. The control module determines the level of the engine oil using the signal from a switch used to monitor the engine oil level. 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. This number is calculated by the control module based on many inputs and is displayed as a percent. The lower the percentage, the shorter the engine oil life.
Engine Oil Pressure Sensor: This parameter displays the voltage signal sent to the control module from the engine oil pressure sensor. The engine oil pressure sensor has a range of values indicating a low oil pressure when the voltage is low to a high oil pressure when the voltage is high.
Engine Oil Pressure Sensor: This parameter displays the pressure of the engine oil as calculated by the control module using a signal from the oil pressure 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 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.
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 Vent Solenoid Command: This parameter displays the state of the evaporative emission (EVAP) vent solenoid commanded by the control module expressed as a Venting or Not Venting. 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.
Extended Travel Brake Pedal Switch: This parameter displays the state of the brake pedal as determined by the extended travel brake pedal switch. The scan tool will display Applied when the brake pedal is depressed greater than approximately 40 percent of the total travel.
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 Relays 2 & 3 Command: This parameter displays the commanded state of the cooling fan relays 2 and 3 control circuit. The cooling fan relays 2 and 3 should be on when the scan tool indicates the FC Relay 2 & 3 Command is On. The cooling fan relays 2 and 3 should be off when the scan tool indicates the FC Relay 2 & 3 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 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 Level Remaining: This parameter displays the amount of fuel remaining in the fuel tank as a percentage. The control module calculates this level using the signal from the sensor used to monitor the fuel level in the fuel tank. The scan tool will display a low reading when the fuel level in the tank is low or near empty. The scan tool will display a high reading when the fuel level in the tank is high or near full.
Fuel Tank Pressure Sensor: This parameter 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 ins 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.