For 1990-2009 cars only
AWD Circuit Status: Displays OK, Short, Open. This parameter
indicates the status of the PWM signal line to the AWD solenoid. The PCM
can detect a short to ground, a short to power, or an open in the
PWM signal line. The AWD Disable lamp will be illuminated for Short
and Open conditions.
AWD Clutch Temp Disable: Displays Yes or No. This parameter displays the status of powertrain software that has the ability to disable AWD based on a rear drive module clutch slip/time calculation. If the software determines that a clutch over-temperature condition could exist, the PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid. The AWD System will be re-enabled when the software calculates that the clutch temperatures have dropped sufficiently. The AWD Disable lamp will be illuminated for a Yes condition.
AWD Duty Cycle: Displays a range of 0-100%. This parameter is the commanded state of the AWD solenoid expressed as a percent of ON time. At vehicle start-up, duty cycle will be at 49-90% for 3 seconds. This is referred to as the pull-in duty cycle. After 3 seconds the duty cycle will drop to 16-28% for 30 seconds. This is referred to as the hold-in duty cycle. After each 30 second hold-in period, the duty cycle will be increased to 49-90% for 1/2 second before returning to the hold-in duty cycle. This is to assure solenoid pull-in. These duty cycles are approximations and will vary with available voltage. Duty cycles of 0% may be seen on the scan tool if an AWD Mini Spare Disable condition is active or the PCM has detected a Rear Drive Module abuse condition. Duty cycles of 100% may be seen if AWD Fluid Temp Disable is active.
AWD Fluid Temp Disable: Displays Yes or No. This parameter indicates a fluid over-temperature condition in the rear drive module. When the sump temperature exceeds approximately 110°C (230°F), a pull-up resistor grounds the PWM signal line from the PCM at the AWD solenoid. The pull-up resistor is an integral part of the AWD solenoid. The pull-up resistor will close the valve and command the PCM to illuminate the AWD Disable lamp for a Yes condition. The scan tool will indicate a 100% duty cycle because the pull-up resistor in the valve is bypassing the PCM.
AWD Voltage Disable: Displays Yes or No. This parameter indicates whether the ignition voltage to the AWD solenoid is in the proper range. The ignition voltage range to the AWD solenoid is 9.0 to 16.0 volts. The PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid if the ignition voltage is out of range. The AWD Disable lamp will be illuminated for a Yes condition.
AWD Mini Spare Disable: Displays Yes or No. This parameter indicates whether the ABS module detects a mini spare on the vehicle. The wheel rotational speed difference is detected by the wheel speed sensors of the ABS system. If the ABS module detects a mini spare on the vehicle, the ABS module commands the PCM to deactivate the AWD system via the class 2 data circuit by disabling the PWM signal line to the AWD solenoid. The AWD Disable lamp will be illuminated for a Yes condition. The scan tool will indicate a 0% duty cycle. After the AWD Mini Spare Disable condition has been corrected the vehicle must be driven 1/4 mile in a straight line and then brought to a complete stop before the AWD Disable lamp will be commanded off for a No condition.
AWD Overtemp Delay: Displays Yes or No. This parameter indicates whether the AWD system is in a reset mode following an AWD fluid temperature disable. The RDM resistor senses for an overtemp condition of 110°C (230°F) when this condition is met the RDM resistor grounds the PWM signal. When the RDM resistor sees 95°C (203°F), the resistor releases the PWM ground, and the PCM begins a 10 minute delay. The RDM resistor is an integral part of the AWD solenoid. The AWD Disable lamp will be illuminated for a Yes condition. After the 10 minute delay the PCM will command the AWD Disable lamp off once the PCM senses a vehicle speed sensor input of 0 km/h (0 mph). The AWD disable lamp will be off for a No condition.
AWD Torque Management: Displays Active or Inactive. This is an indication that some form of torque management is being performed to protect the AWD System. If either or both of these powertrain software features are functioning, a service scan tool will display Active.
(AWD) Wheel Speed Disable: Displays Yes or No. This parameter indicates whether the wheel speed data received from the ABS controller is valid. If the ABS module detects an unacceptable wheel speed differential, the PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid. The AWD DISABLE, BRAKE, and ANTI-LOCK Indicators, will be illuminated for a Yes condition. The chime will also sound.
AWD Disable Mileage: Displays mileage. This parameter indicates the vehicle mileage at which the AWD Last Disable condition occurred
Current Gear: Displays 1, 2, 3 or 4. This parameter indicates the current commanded state of the shift solenoid valves.
ECT (Engine Coolant Temperature): Displays -40 to +151°C (-40 to +304°F). The ECT sensor is mounted in the coolant stream and sends engine temperature information to the PCM. The PCM applies 5 volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold, the internal resistance is high, and the PCM monitors a high signal voltage. The PCM interprets this voltage as a cold engine. While the sensor warms, the internal resistance decreases, and the voltage signal will decrease. The PCM interprets the lower voltage as a warm engine.
Engine Speed: Displays 0-8,192 RPM. The engine speed is computed by the PCM from the fuel control reference input--the crankshaft position sensor. This parameter indicates the rotational speed of the engine expressed as revolutions per minute.
Engine Torque: Displays 0-510 N·m (0-376.1 lb ft). This parameter is the torque delivered by the engine.
Gear Ratio: Displays 0.00-3.98. This display is the actual transmission gear ratio as the transmission operates through all DRIVE, REVERSE and PARK/NEUTRAL ranges.
Ignition Voltage: Displays 0.0-25.5 V. This parameter is the system voltage measured by the PCM at the PCM ignition input when the ignition switch is in the RUN position.
Last Disable Reason: Displays only the last AWD disable reason. The possible reasons are Output Controls, Fluid Temp, Clutch Temp, Wheel Speed, Voltage, Mini Spare, ABS System. The Output Controls reason indicates that AWD was last disabled with a service scan tool. Fluid Temp, Clutch Temp, Wheel Speed, Voltage and Mini Spare each have a unique parameter that is described elsewhere in this table. ABS System reason indicates that messages normally sent to the PCM by the ABS Controller are missing.
TFP Sw (Transmission Fluid Pressure Switch): Displays Park, Reverse, Neutral, Drive 4, Drive 3, Drive 2, Drive 1 or Invalid. TFP Sw display represents a decoded status of the three inputs A/B/C to the PCM from the TFP manual valve position switch.
TP (Throttle Position) Angle: Displays 0-100%. The TP angle is computed by the PCM from the TP sensor voltage. The TP angle should display 0% at idle and 100% at wide open throttle (WOT).
Trans. Fluid Temp. (Transmission Fluid Temperature): Displays -40 to +151°C (-40 to +304°F). This display is the temperature conversion of the voltage input signal to the PCM of the TFT. When the TFT is high at 151°C (304°F), the signal voltage is low, 0 volts. When the TFT is low at -40°C (-40°F), the signal voltage is high, 5 volts.
Transmission ISS (Input Shaft Speed): Displays 0-8191 RPM. This parameter is the rotational speed of the transmission input shaft.
Transmission OSS (Output Shaft Speed): Displays 0-8191 RPM. This display indicates the rotational speed of the transmission output shaft as expressed in revolutions per minute.
Vehicle Speed: Displays 0-255 km/h (0-158 mph). This parameter is the vehicle speed sensor (VSS) input signal converted by the PCM to be displayed as vehicle speed in both metric and English units.
AWD Clutch Temp Disable: Displays Yes or No. This parameter displays the status of powertrain software that has the ability to disable AWD based on a rear drive module clutch slip/time calculation. If the software determines that a clutch over-temperature condition could exist, the PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid. The AWD System will be re-enabled when the software calculates that the clutch temperatures have dropped sufficiently. The AWD Disable lamp will be illuminated for a Yes condition.
AWD Duty Cycle: Displays a range of 0-100%. This parameter is the commanded state of the AWD solenoid expressed as a percent of ON time. At vehicle start-up, duty cycle will be at 49-90% for 3 seconds. This is referred to as the pull-in duty cycle. After 3 seconds the duty cycle will drop to 16-28% for 30 seconds. This is referred to as the hold-in duty cycle. After each 30 second hold-in period, the duty cycle will be increased to 49-90% for 1/2 second before returning to the hold-in duty cycle. This is to assure solenoid pull-in. These duty cycles are approximations and will vary with available voltage. Duty cycles of 0% may be seen on the scan tool if an AWD Mini Spare Disable condition is active or the PCM has detected a Rear Drive Module abuse condition. Duty cycles of 100% may be seen if AWD Fluid Temp Disable is active.
AWD Fluid Temp Disable: Displays Yes or No. This parameter indicates a fluid over-temperature condition in the rear drive module. When the sump temperature exceeds approximately 110°C (230°F), a pull-up resistor grounds the PWM signal line from the PCM at the AWD solenoid. The pull-up resistor is an integral part of the AWD solenoid. The pull-up resistor will close the valve and command the PCM to illuminate the AWD Disable lamp for a Yes condition. The scan tool will indicate a 100% duty cycle because the pull-up resistor in the valve is bypassing the PCM.
AWD Voltage Disable: Displays Yes or No. This parameter indicates whether the ignition voltage to the AWD solenoid is in the proper range. The ignition voltage range to the AWD solenoid is 9.0 to 16.0 volts. The PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid if the ignition voltage is out of range. The AWD Disable lamp will be illuminated for a Yes condition.
AWD Mini Spare Disable: Displays Yes or No. This parameter indicates whether the ABS module detects a mini spare on the vehicle. The wheel rotational speed difference is detected by the wheel speed sensors of the ABS system. If the ABS module detects a mini spare on the vehicle, the ABS module commands the PCM to deactivate the AWD system via the class 2 data circuit by disabling the PWM signal line to the AWD solenoid. The AWD Disable lamp will be illuminated for a Yes condition. The scan tool will indicate a 0% duty cycle. After the AWD Mini Spare Disable condition has been corrected the vehicle must be driven 1/4 mile in a straight line and then brought to a complete stop before the AWD Disable lamp will be commanded off for a No condition.
AWD Overtemp Delay: Displays Yes or No. This parameter indicates whether the AWD system is in a reset mode following an AWD fluid temperature disable. The RDM resistor senses for an overtemp condition of 110°C (230°F) when this condition is met the RDM resistor grounds the PWM signal. When the RDM resistor sees 95°C (203°F), the resistor releases the PWM ground, and the PCM begins a 10 minute delay. The RDM resistor is an integral part of the AWD solenoid. The AWD Disable lamp will be illuminated for a Yes condition. After the 10 minute delay the PCM will command the AWD Disable lamp off once the PCM senses a vehicle speed sensor input of 0 km/h (0 mph). The AWD disable lamp will be off for a No condition.
AWD Torque Management: Displays Active or Inactive. This is an indication that some form of torque management is being performed to protect the AWD System. If either or both of these powertrain software features are functioning, a service scan tool will display Active.
(AWD) Wheel Speed Disable: Displays Yes or No. This parameter indicates whether the wheel speed data received from the ABS controller is valid. If the ABS module detects an unacceptable wheel speed differential, the PCM will deactivate the AWD system by disabling the PWM signal line to the AWD solenoid. The AWD DISABLE, BRAKE, and ANTI-LOCK Indicators, will be illuminated for a Yes condition. The chime will also sound.
AWD Disable Mileage: Displays mileage. This parameter indicates the vehicle mileage at which the AWD Last Disable condition occurred
Current Gear: Displays 1, 2, 3 or 4. This parameter indicates the current commanded state of the shift solenoid valves.
ECT (Engine Coolant Temperature): Displays -40 to +151°C (-40 to +304°F). The ECT sensor is mounted in the coolant stream and sends engine temperature information to the PCM. The PCM applies 5 volts to the ECT sensor circuit. The sensor is a thermistor which changes internal resistance as temperature changes. When the sensor is cold, the internal resistance is high, and the PCM monitors a high signal voltage. The PCM interprets this voltage as a cold engine. While the sensor warms, the internal resistance decreases, and the voltage signal will decrease. The PCM interprets the lower voltage as a warm engine.
Engine Speed: Displays 0-8,192 RPM. The engine speed is computed by the PCM from the fuel control reference input--the crankshaft position sensor. This parameter indicates the rotational speed of the engine expressed as revolutions per minute.
Engine Torque: Displays 0-510 N·m (0-376.1 lb ft). This parameter is the torque delivered by the engine.
Gear Ratio: Displays 0.00-3.98. This display is the actual transmission gear ratio as the transmission operates through all DRIVE, REVERSE and PARK/NEUTRAL ranges.
Ignition Voltage: Displays 0.0-25.5 V. This parameter is the system voltage measured by the PCM at the PCM ignition input when the ignition switch is in the RUN position.
Last Disable Reason: Displays only the last AWD disable reason. The possible reasons are Output Controls, Fluid Temp, Clutch Temp, Wheel Speed, Voltage, Mini Spare, ABS System. The Output Controls reason indicates that AWD was last disabled with a service scan tool. Fluid Temp, Clutch Temp, Wheel Speed, Voltage and Mini Spare each have a unique parameter that is described elsewhere in this table. ABS System reason indicates that messages normally sent to the PCM by the ABS Controller are missing.
TFP Sw (Transmission Fluid Pressure Switch): Displays Park, Reverse, Neutral, Drive 4, Drive 3, Drive 2, Drive 1 or Invalid. TFP Sw display represents a decoded status of the three inputs A/B/C to the PCM from the TFP manual valve position switch.
TP (Throttle Position) Angle: Displays 0-100%. The TP angle is computed by the PCM from the TP sensor voltage. The TP angle should display 0% at idle and 100% at wide open throttle (WOT).
Trans. Fluid Temp. (Transmission Fluid Temperature): Displays -40 to +151°C (-40 to +304°F). This display is the temperature conversion of the voltage input signal to the PCM of the TFT. When the TFT is high at 151°C (304°F), the signal voltage is low, 0 volts. When the TFT is low at -40°C (-40°F), the signal voltage is high, 5 volts.
Transmission ISS (Input Shaft Speed): Displays 0-8191 RPM. This parameter is the rotational speed of the transmission input shaft.
Transmission OSS (Output Shaft Speed): Displays 0-8191 RPM. This display indicates the rotational speed of the transmission output shaft as expressed in revolutions per minute.
Vehicle Speed: Displays 0-255 km/h (0-158 mph). This parameter is the vehicle speed sensor (VSS) input signal converted by the PCM to be displayed as vehicle speed in both metric and English units.
