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 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 Disengage 1-8 History
- The parameter displays the last 8 air conditioning (A/C) compressor disengages in order from 1 to 8 with 8 being the most recent. There are about 8 possible causes for the A/C compressor to disengage.

A/C High Side Pressure
- This parameter displays the voltage from the A/C high side pressure sensor signal circuit to the control module.

A/C High Side Pressure
- This parameter displays the pressure from the A/C high side pressure sensor signal circuit to the control module.

A/C Off for WOT
- This parameter displays whether the control module is commanding the A/C compressor clutch relay off for wide open throttle (WOT).

A/C Pressure Disable
- This parameter displays whether the A/C pressure is out of range for normal operation as determined by the control module.

A/C Relay Circuit Status
- This parameter displays the state of the air conditioning (A/C) clutch relay control circuit. The parameter displays Fault if the A/C clutch relay control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

A/C Relay Command
- This parameter displays the state of the air conditioning (A/C) clutch relay control circuit as commanded by the control module.

A/C Request Signal
- This parameter displays the state of the A/C request input to the control module from the heating, ventilation, and air conditioning (HVAC) controls.

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 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.

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 using the signals from the APP sensors.

APP Sensor 1
- This parameter displays the actual voltage on the accelerator pedal position (APP) sensor 1 signal circuit as measured by the control module.

APP Sensor 2
- This parameter displays the actual voltage on the accelerator pedal position (APP) sensor 2 signal circuit as measured by the control module.

APP Sensor 1 and 2
- This parameter displays Disagree if the control module detects the signal voltage from APP sensor 1 is not in correct relationship to APP sensor 2. The scan tool displays Agree under the normal operating conditions.

BARO
- This parameter displays the barometric pressure. The control module uses the barometric pressure sensor input for fuel control to compensate for altitude differences.

BARO
- This parameter displays the barometric pressure sensor voltage.

Brake Pedal Signal Status
- This parameter displays the serial data message of the brake signal from the electronic brake and traction control module (EBTCM).

Calculated ECT - Closed Loop Fuel Control
- This parameter displays the modeled temperature that the control module calculates from air entering the engine, coolant temperature, and ambient air temperature. If the actual engine coolant temperature does not reach this calculated temperature within a predetermined amount of time, a DTC will set.

Calculated ECT - Thermostat Diagnosis
- This parameter displays the modeled temperature that the control module calculates from air entering the engine, coolant temperature, and ambient air temperature. If the actual engine coolant temperature does not reach this calculated temperature within a predetermined amount of time, a DTC will set.

Calc. TWC Temp. Bank 1 or Bank 2
- This parameter displays the catalytic converter temperature as calculated by the control module.

Catalytic Converter Protection Active
- This parameter displays if the control module is commanding catalytic converter protection.

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.

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

Clutch Start Switch (If Equipped)
- This parameter displays the state of the clutch pedal as determined by the control module from the clutch start switch.

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

Cold Start up
- This parameter displays the state of the engine coolant temperature at start up.

CPP Switch (If Equipped)
- This parameter displays the state of the clutch pedal as determined by the control module from the clutch pedal switch.

Crank Request Signal
- This parameter displays whether the ignition switch has been cycled to the crank position requesting the control module to activate the starter relay.

Cruise Control Active
- This parameter displays the status of the cruise control system as determined by the control module.

Cruise Disengage 1-8 History
- The parameter displays the last 8 cruise control disengages in order from 1 to 8, with 8 being the most recent. There are about 33 possible causes for the cruise control to disengage.

Cruise Inhibited
- This parameter displays the status of the cruise control system as determined by the control module.

Cruise On/Off Switch
- This parameter displays the status of the cruise control system as determined by the control module.

Cruise Resume/Accel. Switch
- This parameter displays the status of the cruise control system as determined by the control module.

Cruise Set/Coast Switch
- This parameter displays the status of the cruise control system as determined by the control module.

Cylinder 1-6 IC Circuit Status
- This parameter displays the diagnostic state of the output driver for the ignition control circuits. The scan tool will display OK if the circuit is operating correctly. The scan tool will display Short or Open 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 state of the fuel injector control circuit. The parameter displays Fault if the fuel injector control circuit is open, shorted to ground, or shorted to voltage.

Cylinder 1-6 Knock Retard
- This parameter displays the knock retard as commanded by the control module for cylinders 1-6. Each cylinder is controlled individually based on both knock sensor signal inputs.

Decel. Fuel Cutoff
- This parameter displays the status of the operating mode of the control module used to turn off the fuel injectors and the EVAP canister purge valve during certain deceleration conditions.

Desired Exh. CMP Bank 1 or 2
- This parameter displays the desired exhaust camshaft angle as commanded by the control module.

Desired HO2S Bank 1 or 2 Sensor 1
- This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

Desired Idle Speed
- This parameter displays the desired engine idle speed as commanded by the control module.

Desired Int. CMP Bank 1 or 2
- This parameter displays the desired intake camshaft angle as commanded by the control module.

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.

DTC Set This Ignition
- This parameter displays Yes if a DTC set on the current ignition cycle.

EC Ignition Relay Command
- This parameter displays the state of the control circuit for control module power relay as commanded by the control module.

EC Ignition Relay Circuit Status
- This parameter displays the state of the EC Ignition Relay control circuit. The parameter displays Fault if the EC Ignition Relay control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

EC Ignition Relay Feedback Signal
- This parameter displays the voltage available at the EC ignition relay pin of the control module.

ECM in VTD Fail Enable
- This parameter indicates whether or not the engine control module (ECM) is in failure enable mode for the vehicle theft deterrent (VTD) system.

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

Engine Load
- This parameter displays the calculated engine load in percent based on inputs to the control module from various engine sensors.

Engine Off EVAP Test Conditions Met
- This parameter displays Yes if the conditions for running the Engine Off EVAP diagnostic are met.

Engine Off Time
- This parameter displays the amount of time that has elapsed since the engine was last cycled OFF.

Engine Oil Life Remaining
- This parameter displays the percent of engine oil life remaining. The controller calculates the engine oil life by monitoring engine load, coolant temperature, and engine speed.

Engine Oil Pressure Sensor
- This parameter displays the voltage signal received by the control module from the engine oil pressure (EOP) sensor.

Engine Oil Pressure Sensor
- This parameter displays the engine oil pressure.

Engine Oil Temperature Calculated
- This parameter displays the engine oil temperature.

Engine Run Time
- This parameter displays the time elapsed since the engine was started.

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.

Engine Speed
- This parameter displays the speed of the engine crankshaft rotation from information received from the crankshaft position (CKP) sensor. If there is a CKP sensor DTC, the ECM calculates the engine speed from one of the camshaft position (CMP) sensors.

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 state of the evaporative emission (EVAP) purge solenoid control circuit. The parameter displays Fault if the EVAP purge solenoid control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

EVAP Purge Solenoid Command
- This parameter displays the on-time or duty cycle of the EVAP canister purge solenoid commanded by the control module. Zero percent indicates no purge. One hundred percent indicates full purge.

EVAP Vent Solenoid Circuit Status
- This parameter displays the state of the EVAP vent solenoid control circuit. The parameter displays Fault if the EVAP vent solenoid control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON. This parameter may not change if the scan tool is used to command the EVAP vent solenoid ON.

EVAP Vent Solenoid Command
- This parameter displays the state of the control circuit for evaporative emission (EVAP) vent solenoid as commanded by the control module.

Exh. CMP Angle Bank 1 or 2
- This parameter displays the actual exhaust camshaft position in degrees.

Exh. CMP Bank 1 or Bank 2 Active Counter
- This parameter displays an incrementing counter when the control module receives a signal from the exhaust camshaft position (CMP) sensor.

Exh. CMP Bank 1 or 2 Command
- This parameter displays the exhaust camshaft position in percent of range as commanded by the control module.

Exh. CMP Angle Bank 1 or 2 Variance
- This parameter displays in degrees, the difference between the desired exhaust camshaft position and the actual exhaust camshaft position.

Exh. CMP Solenoid Bn. 1 or 2 Circuit Status
- This parameter displays the state of the exhaust camshaft actuator solenoid control circuit. The parameter displays Fault if the camshaft actuator solenoid control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

FC Relay 1 Circuit Status
- This parameter displays the state of the fan relay control circuit. The parameter displays Fault if the fan relay control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

FC Relay 2 and 3 Circuit Status
- This parameter displays the state of the fan relay control circuit. The parameter displays Fault if the fan relay control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the relay control circuit has been commanded ON.

FC Relay 1 Command
- This parameter displays the control module commanded state of the fan relay control circuit.

FC Relay 2 and 3 Command
- This parameter displays the control module commanded state of the fan relay control circuit.

Fuel Level Sensor Left Tank (Secondary) Right Tank (Primary)
- This parameter displays the voltage signal received by the control module from the fuel level sensors.

Fuel Pump Relay Circuit Status
- This parameter displays the state of the fuel pump relay control circuit. The parameter displays Fault if the fuel pump relay control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

Fuel Pump Relay Command
- This parameter displays the control modules commanded state of the fuel pump relay control circuit.

Fuel Tank Level Remaining
- This parameter displays the amount of fuel in liters/gallons that remains in the fuel tank as determined by the control module from information received from the left and right fuel level sensors.

Fuel Tank Pressure Sensor
- This parameter displays the pressure/vacuum inside the fuel tank. A negative value indicates a vacuum, while a positive value indicates a pressure.

Fuel Tank Pressure Sensor
- This parameter displays the voltage signal received by the control module from the fuel tank pressure (FTP) sensor.

Fuel Tank Rated Capacity
- This parameter displays the capacity of the fuel tank in liters or gallons.

Fuel Trim Learn
- This parameter displays Enabled when conditions are appropriate for enabling long term fuel trim corrections. This indicates that the long term fuel trim is adapting continuing amounts of short term fuel trim. If the scan tool displays Disabled, then long term fuel trim will not respond to changes in short term fuel trim.

GEN L-Terminal Signal Command
- This parameter displays the control modules commanded state of the voltage regulator on the generator.

Generator F-Terminal Signal
- This parameter displays the amount of generator on-time as commanded by the control module. The higher the percentage the greater the generator output.

HO2S Bank 1 or 2 Sensor 1
- This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

HO2S Bank 1 or 2 Sensor 2
- This parameter displays the voltage output from the HO2S to the control module. A lower voltage indicates a lean exhaust, while a higher voltage indicates a rich exhaust.

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 Htr. Bn. 1 or 2 Sensor 1 or 2 Circuit Status
- This parameter displays the state of the oxygen sensor heater control circuit. The parameter displays Fault if the oxygen sensor heater control circuit is open, shorted to ground, or shorted to voltage. The parameter displays Indeterminate until the circuit has been commanded ON.

HO2S Bank 1 or 2 Sensor 1 or 2 Heater Command
- This parameter displays the commanded state of the HO2S Bank 1 or 2 Sensor 1 or 2 by the control module. The scan tool will display a higher value as the heater command is increased, and a lower value if the heater is not commanded ON.

HO2S Bank 1 or 2 Sensor 1 or 2 Heater Command
- This parameter displays the commanded state of the Bank 2 Sensor 1 heater 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/O2S Monitor Complete This Ignition
- This parameter displays the diagnostic monitor completion status during the current driving/monitoring cycle.

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

HO2S Sensing Element Bn. 1 or 2 Sensor 1 or 2
- This parameter displays the resistance of the sensing element within the control module. The front sensors are normally regulated to 80 ohms. The rear sensors are normally regulated between 20-300 ohms which depends on temperature.

HO2S Sensor 1 module Signal
- This parameter displays the voltage of the HO2S control transistor, which is internal to the ECM.