Part 1

Scan Tool Data Definitions

The Engine Scan Tool Data Definitions contains a brief description of all engine related parameters available on the scan tool. The list is arranged in alphabetical order. A given parameter may appear in any one of the data lists. In some cases, the parameter may appear more than once or in more than one data list in order to group certain related parameters together.

5-Volt 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-Volt 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-Volt 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-Volt 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.

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).

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 Sensors
- 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 listed in percent.

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 Sensors 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 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.

Calc. TWC Temp. Bank 1
- Calculated catalytic converter temperature.

Calc. TWC Temp. Bank 2
- Calculated catalytic converter temperature.

Catalyst Monitor Complete This Ignition
- This parameter displays the monitor completion status during the current driving/monitoring cycle.

Catalyst Monitor Enabled This Ignition
- This parameter displays the monitor enable status during the current driving/monitoring cycle.

Catalytic Converter Protection Active
- This parameter displays the state of the Catalytic Converter Protection 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.

Cmmd. 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.

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

CMP Angle
- This parameters shows the actual amount, in camshaft degrees, of camshaft actuation.

CMP Command
- This parameters shows the commanded percentage of the CMP actuator, by the control module.

CMP Sensor
- This parameter displays the speed of the engine as calculated by the signal from the camshaft position (CMP) sensor, shown in RPM.

CMP Variance
- This parameter shows the difference, in degrees of camshaft actuation, between the desired camshaft position and the actual position.

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.

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 and 4 IC Circuit Status
- This parameter displays the status of the output driver for the ignition control circuits. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

Cylinder 2 and 5 IC Circuit Status
- This parameter displays the status of the output driver for the ignition control circuits. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

Cylinder 3 and 6 IC Circuit Status
- This parameter displays the status of the output driver for the ignition control circuits. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Fault if there is an open, short to ground or a short to voltage on the circuit.

Cylinder 1-6 Injector Circuit Status
- This parameter displays the current status 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 CMP
- This parameter displays the desired camshaft position, in degrees, as calculated by the control module.

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

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

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 Fault History
- This parameter displays the result of the evaporative emission (EVAP) system diagnostic.
Scan tool displays NO FAULT, EXCESS VACUUM, PURGE VALVE LEAK, SMALL LEAK, or WEAK VACUUM. The EVAP Fault History indicates the status of EVAP system diagnostics performed by the PCM.

EVAP Monitor Complete This Ignition
- This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

EVAP Monitor Enabled This Ignition
- This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

EVAP Purge Solenoid Circuit Status
- This parameter displays the status of the output driver for the evaporative emission purge 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.

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 Vent Solenoid Circuit Status
- This parameter displays the status of the output driver for the evaporative emission vent 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.

EVAP Vent Solenoid Command
- This parameter displays the state of the 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.

Fuel Level Sensor
- This parameter displays the approximate fuel level in the fuel tank as a voltage. 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 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 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 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 indicates 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.

HO2S Bank 1 Sensor 1
- A YES display indicates that the oxygen sensor is warmed up and is capable of sending useful voltage readings to the PCM. A NO display indicates a cold (not ready) oxygen sensor.
Indicates the status of the fuel control exhaust oxygen sensor. The scan tool will indicate that the exhaust oxygen sensors are ready when the PCM detects a fluctuating heated oxygen sensor (HO2S) voltage sufficient to allow closed loop operation. This will not occur unless the exhaust oxygen sensors are warmed up.

HO2S Bank 1 Sensor 2
- The scan tool displays mV.
The scan tool displays a range of 0-1,106 mV. The HO2S bank 2 sensor 2 parameter represents the exhaust oxygen sensor output voltage. The voltage fluctuates constantly within a range between 10 mV, and 1,000 mV, while operating in Closed Loop.
The scan tool displays 0 to 1275 mV. This parameter is the actual voltage on the HO2S signal circuit as measured by the ECM.

HO2S Bank 2 Sensor 1
- This parameter indicates the 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 2 Sensor 2
- This parameter indicates the HO2S bank 1 sensor 2 output voltage as measured by the control module. The scan tool will display a higher value during rich running conditions, and a lower value during leaner running conditions.
The post-catalyst HO2S output voltage will fluctuate slowly over a longer period of time, compared to the fuel control oxygen sensor s. This is due to the oxygen storage capacity of an efficiently operating catalyst.
The scan tool displays 0 to 1275 mV. This parameter is the actual voltage on the HO2S signal circuit as measured by the control module.

HO2S Bank 1 Sensor 1 Heater Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 1 sensor 1. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Bank 1 Sensor 2 Heater Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 1 sensor 2. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Bank 2 Sensor 1 Heater Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 2 sensor 1. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Bank 2 Sensor 2 Heater Command
- This parameter displays the commanded state of the heater control circuit for oxygen bank 2 sensor 2. The oxygen sensor heater should be on when the scan tool indicates the HO2S Heater Command is On. The oxygen sensor heater should be off when the scan tool indicates the HO2S Heater Command is Off.

HO2S Bank 1 Sensor 1 Heater
- 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 Bn 1 Sen. 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Bank 1 Sensor 2 Heater
- 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 Bn 1 Sen. 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Bank 2 Sensor 1 Heater
- 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 Bn 2 Sen. 1 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Bank 2 Sensor 2 Heater
- 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 Bn 2 Sen. 2 is a range of values indicating a low current when the heater circuit resistance is high to a high current when the heater circuit resistance is low.

HO2S Bank 1 Sensor 1 Heater Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 1 Sen. 1. 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.

HO2S Bank 1 Sensor 2 Heater Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 1 Sen. 2. 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.

HO2S Bank 2 Sensor 1 Heater Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 2 Sen. 1. 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.

HO2S Bank 2 Sensor 2 Heater Circuit Status
- This parameter displays the status of the output driver for the HO2S Heater Bn 2 Sen. 2. 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.

HO2S Heater Monitor Complete This Ignition
- This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

HO2S Heater Monitor Enabled This Ignition
- This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

HO2S/O2S Monitor Complete This Ignition
- This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

HO2S/O2S Monitor Enabled This Ignition
- This parameter displays the diagnostic monitor enable status during the current driving/monitoring cycle.

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.