A/C - F

The Engine Scan Tool Data Definitions contains 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 Feed Back Signal: The scan tool displays relay ON or relay OFF. This parameter displays the signal received from the A/C clutch to the powertrain control module (PCM) to indicate the A/C clutch relay is ON or OFF.

A/C Compressor Cycling Switch: The scan tool displays Low Pressure or Normal. This parameter displays the state of the A/C compressor cycling switch. The A/C compressor cycling switch is a normally closed switch.

A/C Sec. High Pressure Switch: The scan tool displays High Pressure or Normal. This parameter displays the state of the A/C secondary high pressure switch. The A/C secondary high pressure switch is normally open.

A/C Relay Command: The scan tool displays ON or OFF. This parameter displays the powertrain control module (PCM) commanded state of the A/C clutch control relay. When the scan tool displays ON, the A/C clutch should be engaged.

A/C Request Signal: The scan tool displays Yes or No. The A/C Request displays the state of the A/C request input circuit from the heating, ventilation, and air conditioning (HVAC) controls. The powertrain control module (PCM) uses the A/C request signal in order to determine whether the A/C compressor operation is being requested.

APP Average: The scan tool displays 0-125 counts. The throttle actuator control (TAC) module takes the voltages from the 3 accelerator pedal position (APP) sensors, averages the readings, and converts the readings into counts. The scan tool displays the average. The average is different on every vehicle.

APP Indicated Angle: The scan tool displays 0-100 percent. The scan tool displays the accelerator pedal position (APP) in percentage. When the APP is at rest, the display shows 0 percent. When the APP is fully depressed, the display shows 100 percent.

APP Sensor 1: The scan tool displays 0-5 volts. When the accelerator pedal is at 0 percent, pedal at rest, the display shows less than 1.1 volt. When the accelerator pedal is at 100 percent, pedal fully depressed, the display shows more than 2 volts.

APP Sensor 1: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the throttle actuator control (TAC) module the actual pedal position.

APP Sensor 2: The scan tool displays 5-0 volts. When the accelerator pedal is at 0 percent, pedal at rest, the display shows more than 3.9 volts. When the accelerator pedal is at 100 percent, pedal fully depressed, display shows less than 3.0 volts.

APP Sensor 2: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the throttle actuator control (TAC) module the actual pedal position

APP Sensor 3: The scan tool displays 5-0 volts. When the accelerator pedal is at 0 percent, pedal at rest, display shows more than 3.2 volts. When the accelerator pedal is at 100 percent, pedal fully depressed, display shows less than 3.5 volts.

APP Sensor 3: The scan tool displays 0-100 percent. When the accelerator pedal is at rest, display shows 0 percent. When the accelerator pedal is fully depressed, display shows 100 percent. This percentage indicates to the throttle actuator control (TAC) module the actual pedal position.

APP Sen. 1 and 2: The scan tool displays Agree or Disagree. When the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 1 not in proper relationship to APP sensor 2, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

APP Sen. 1 and 3: The scan tool displays Agree or Disagree. When the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 1 not in proper relationship to APP sensor 3, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

APP Sen. 2 and 3: The scan tool displays Agree or Disagree. When the throttle actuator control (TAC) module receives a signal voltage from accelerator pedal position (APP) sensor 2 not in proper relationship to APP sensor 3, the scan tool displays Disagree. The scan tool displays Agree under the normal operating conditions.

Auxiliary Fan Request: The scan tool displays ON or OFF. The scan tool displays ON when the powertrain control module (PCM) grounds the auxiliary fan relay control circuit. The scan tool displays OFF when the PCM disables the ground circuit.

BARO: The scan tool displays a range of 10-105 kPa. The barometric pressure (BARO) reading is determined from the manifold absolute pressure (MAP) sensor signal. The powertrain control module (PCM) monitors the MAP signal during key up or wide open throttle (WOT) conditions. The barometric pressure (BARO) compensates for altitude differences.

CMP Sensor-High to Low: The scan tool displays 0-65,535 counts. The counts increment as the powertrain control module (PCM) detects the camshaft position (CMP) sensor signal voltage going from high to low.

CMP Sensor-Low to High: The scan tool displays 0-65,535 counts. The counts increment as the powertrain control module (PCM) detects the camshaft position (CMP) signal voltage going from low to high.

Cold Start Up: The scan tool displays Yes or No. A cold start-up is when the engine coolant temperature (ECT) rises above a predetermined temperature during an ignition cycle. The next ignition cycle the ECT should be below a predetermined temperature. Also the ECT and the intake air temperature (IAT) are less than 50°C (122°F) and are within 3°C (5°F) of each other at start-up. When the above is true, the scan tool displays Yes.

Coolant Level Switch: The scan tool displays OK or Low. This parameter indicates when the engine coolant level is low. The scan tool displays Low when the powertrain control module (PCM) detects the engine coolant level is low.

Cruise Control Active: The scan tool displays Yes or No. When the cruise control switch is ON and the set/coast switch is activated, the scan tool displays yes. When the cruise control switch is ON and the set/coast switch is released, the scan tool displays No.

Cruise On/Off Switch: The scan tool displays ON or OFF. When you activate the cruise control switch, the scan tool displays ON. The switch, when in the ON position, sends a signal voltage to the throttle actuator control (TAC) module. This allows all other functions of the cruise control. When you turn OFF the cruise control switch, the scan tool displays OFF.

Cruise Resume/Accel: The scan tool displays ON or OFF. 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: The scan tool displays ON or OFF. 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: The scan tool displays 0-4. The scan tool displays which gear the transmission is in. An illegal transmission position displays 9.

Cycles of Misfire Data: The scan tool displays a range of 0-100. The powertrain control module (PCM) counts the number of misfire tests during 200 engine revolutions.

Desired EGR Position: The scan tool displays 0-100 percent. This parameter displays the desired position of the exhaust gas recirculation (EGR) pintle as requested by the powertrain control module (PCM). This parameter should be very close to actual EGR position.

Desired EGR Position: The scan tool displays 0-5 volts. The commanded exhaust gas recirculation (EGR) is the EGR pintle position commanded by the powertrain control module (PCM).

Desired Idle Speed: The scan tool displays a range of 0-3,187 RPM. The powertrain control module (PCM) commands the desired idle speed. The PCM compensates for various engine loads based on engine coolant temperature (ECT) in order to keep the engine at the desired speed.

DTC Set This Ignition: The scan tool displays Yes or No. This parameter indicates if a DTC set during the current ignition cycle.

ECT Sensor: The scan tool displays a range of -39 to +140°C (-38 to +284°F). The powertrain control module (PCM) applies 5 volts to the engine coolant temperature (ECT) sensor circuit. The sensor is a thermistor which changes internal resistance as the engine temperature changes. When the sensor is cold, internal resistance high, the PCM senses a high signal voltage and interprets the voltage as a cold engine. As the sensor warms, internal resistance decreases, the voltage signal decreases and the PCM interprets the lower voltage as a warm engine.

EGR Closed Valve Pintle Position: The scan tool displays 0-5 volts. This display represents the voltage that the powertrain control module (PCM) uses in order to determine whether or not the exhaust gas recirculation (EGR) valve is closed. The voltage displayed will be the closed position of the EGR pintle learned by the PCM.

EGR Position Sensor: The scan tool displays 0-5 volts. This parameter displays the actual exhaust gas recirculation (EGR) pintle position in voltage.

EGR Position Sensor: The scan tool displays a range of 0-100 percent. The powertrain control module (PCM) supplies a pulse width modulated (PWM) duty cycle to control the exhaust gas recirculation (EGR) valve. Zero percent indicates no EGR flow. One hundred percent indicates full EGR flow.

Engine Load: The scan tool displays a range of 0-100 percent. The powertrain control module (PCM) calculates the engine load from engine speed and mass airflow (MAF) sensor readings. The engine load increases with an increase in RPM or airflow.

Engine Oil Level Switch: The scan tool displays OK or Low. This parameter indicates when the engine oil level is low. The scan tool displays Low when the powertrain control module (PCM) detects the engine oil level is low.

Engine Oil Life Remaining: The scan tool displays 0-100 percent. This display represents the engine oil life index that is calculated and maintained by the powertrain control module (PCM).

Engine Run Time: The scan tool displays Hours, Minutes and Seconds. This displays the amount of engine run time for the current ignition cycle. When you cycle the ignition OFF, the timer resets to zero.

Engine Speed: The scan tool displays a range of 0-10,000 RPM. The powertrain control module (PCM) computes engine speed from the ignition reference pulses. The engine speed should remain close to desired idle under various engine loads with the engine idling.

EVAP Purge Solenoid Command: The scan tool displays a range of 0-100 percent. The powertrain control module (PCM) supplies a pulse width modulated (PWM) duty cycle to control the evaporative emission (EVAP) purge solenoid valve. 0 percent indicates no purge. 100 percent indicates full purge.

EVAP Test Result: The scan tool displays if the evaporative emission (EVAP) test has passed or failed. The scan tool displays pass when the powertrain control module (PCM) determines that the EVAP diagnostic has passed. The scan tool displays fail when the PCM determines that the EVAP diagnostic has failed.

EVAP Vent Solenoid Command: The scan tool displays Venting or Not Venting. The evaporative emission (EVAP) canister vent valve is normally open. The powertrain control module (PCM) commands the EVAP canister vent valve closed, during testing of the EVAP system.

Fuel Level Sensor: This parameter displays the voltage signal sent to the control module from the primary fuel tank level sensor. Fuel Level Sensor is a range of values indicating a high voltage when the fuel level is high to a low voltage when the fuel level is low (near empty).

Fuel Level Sensor Rear Tank (If Equipped): This parameter displays the voltage signal sent to the control module from the secondary (rear) fuel tank level sensor. Fuel Level Sensor is a range of values indicating a high voltage when the fuel level is high to a low voltage when the fuel level is low (near empty).

Fuel Tank Level Remaining: This parameter displays the total fuel remaining as calculated by the control module using the signal primary and secondary fuel level sensors. Fuel Tank Level Remaining is a range of values indicating a low quantity when the fuel tanks are near empty to a high quantity when the fuel tanks are near full.

Fuel Tank Level Remaining: This parameter displays the total fuel remaining as calculated by the control module using the signal primary and secondary fuel level sensors. Fuel Tank Level Remaining is a range of values indicating a low percentage when the fuel tanks are near empty to a high percentage when the fuel tanks are near full.

Fuel Tank Pressure Sensor: The scan tool displays -32.7 to +13.96 mm/Hg (-17.4 to +7.5 in H2O). This parameter indicates the pressure vacuum inside of the fuel tank. A negative value indicates a vacuum. A positive value indicates a pressure.

Fuel Tank Pressure Sensor: The scan tool displays 0-5 volts. The scan tool displays in voltage the pressure inside of the fuel tank.

Fuel Tank Rated Capacity: The scan tool displays the capacity of the fuel tank in liters or gallons.

Fuel Trim Cell: The scan tool displays a range of 0-23. The powertrain control module (PCM) determines from the manifold absolute pressure (MAP) and RPM inputs which fuel trim cell to operate the engine in. The fuel trim cell displayed on the scan tool is the cell that the engine is operating under.

Fuel Trim Learn: The scan tool displays Enabled or Disabled. When conditions are appropriate for enabling long term fuel trim corrections, the scan tool displays Enabled. This indicates that the long term fuel trim is responding to the 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.