Pinpoint Test A: All-Wheel Drive (AWD) System Functional Test

WARNING: This page is about a different car, the 2010 Mercury Mariner and 2010 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

WARNING: When directed to drive the vehicle as part of this test, drive the vehicle on a hard surface in an area without traffic to prevent a crash. Failure to follow these instructions may result in personal injury.

NOTE: Carry out a thorough inspection and verification as outlined before carrying out this pinpoint test. Refer to INSPECTION AND VERIFICATION .

A1 CHECK FOR WRENCH LIGHT PROVE-OUT
- Turn the ignition to the ON position and observe the wrench light.
- Does the wrench light illuminate for 3 seconds and then turn OFF?
- Yes: GO to A2 .
- No: REFER to DIAGNOSIS AND TESTING for further diagnosis of the Instrument Cluster (IC).
A2 CHECK FOR ATC SOLENOID (PART OF REAR AXLE) LOCK
- Drive the vehicle on a dry, hard surface in turns while applying the accelerator pedal.
- Is driveline wind-up present in turns?
- Yes: With the ignition switch in ON position, allow the Active Torque Coupling (ATC) solenoid to cool down for at least 10 minutes and repeat the test. CHECK for wind-up again. If no wind-up is found, GO to A3 . If still present, GO to PINPOINT TEST E .
- No: GO to A3 .
A3 CHECK FOR VALID ACCELERATOR PEDAL POSITION MONITORING THE ACCELERATOR PEDAL POSITION (AP) PID
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Monitor the AP PID while pressing the accelerator pedal.
- Does the accelerator pedal position match the AP PID percent value?
- Yes: GO to A4 .
- No: REFER to the INTRODUCTION - GASOLINE MODELS to diagnose the accelerator pedal position sensor concern.
A4 CHECK 4X4 CONTROL MODULE WHEEL SPEED SENSOR PIDs
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- While driving the vehicle at 48 km/h (30 mph), monitor the following wheel speed sensor PIDs:
  - Left Front Wheel Speed Sensor (LF_WSPD)
  - Left Rear Wheel Speed Sensor (LR_WSPD)
  - Right Front Wheel Speed Sensor (RF_WSPD)
  - Right Rear Wheel Speed Sensor (RR_WSPD)
- Are all 4 wheel speeds within 2 km/h (1.2 mph) of each other?
- Yes: GO to A5 .
- No: GO to PINPOINT TEST F .
A5 CHECK VEHICLE ACCELERATION IN A STRAIGHT LINE
- Carry out 3 accelerations from 0-48 km/h (0-30 mph) in a straight line (one each with low, medium and full accelerator pedal application).
- Does the vehicle pulsate or shudder while accelerating?
- Yes: GO to PINPOINT TEST E .
- No: GO to A6 .
A6 CHECK VEHICLE TURNING ABILITY
- Drive the vehicle in a fully locked turn, on dry pavement, at 8 km/h (5 mph).
- Does the vehicle bind in the turn or resist turning?
- Yes: GO to PINPOINT TEST E .
- No: GO to A7 .
A7 CHECK FOR TORQUE AT REAR WHEELS USING PWM OUTPUT CONTROL COMMAND #1 (CLCH_SOL) ACTIVE COMMAND
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Using the scan tool, command CLCH_ SOL to energize the ATC solenoid to a constant 100% applied.
- Drive the vehicle in a fully locked turn, on dry pavement, at 8 km/h (5 mph).
- Does the vehicle bind in the turn or resist turning?
- Yes: END the active command. The concern can not be duplicated at this time. RETURN the vehicle to the customer.
- No: END the active command. CHECK that the driveshaft rotates when the transaxle is in gear. If yes, GO to PINPOINT TEST D . If no, CHECK the Power Transfer Unit (PTU). REFER to DIAGNOSIS AND TESTING .