Pinpoint Test E: Vehicle Binds In A Turn or Resists Turning/Pulsates or Shudders In A Straight Line
Four Wheel Drive (4WD) Systems
Pinpoint Tests
Pinpoint Test E: Vehicle Binds in a Turn or Resists Turning/Pulsates or Shudders in a Straight Line
Refer to Wiring Diagram Set 34, All Wheel Drive (AWD) for schematic and connector information. Diagrams By Number
Normal Operation
The All-Wheel Drive (AWD) system continuously monitors vehicle conditions and automatically adjusts the torque distribution between the front and rear wheels. During normal operation, most of the torque is sent to the front wheels. If wheel slip between the front and rear wheels is detected or the vehicle is under heavy acceleration, the AWD system increases torque to the rear wheels.
This pinpoint test is intended to diagnose the following:
- Rear axle
- Wheels/tires
- PCM
- ABS module
- 4X4 control module
- Circuitry
PINPOINT TEST E: VEHICLE BINDS IN A TURN OR RESISTS TURNING/PULSATES OR SHUDDERS IN A STRAIGHT LINE
NOTE: Carry out a thorough inspection and verification as outlined before carrying out this pinpoint test.
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E1 CHECK FOR TORQUE AT THE REAR WHEELS
- Ignition OFF.
- Disconnect: Active Torque Coupling (ATC) Solenoid (part of rear axle) C3254.
- Drive the vehicle in a straight line on dry pavement.
- Is a pulsation or shudder still present?
Yes
REFER to Differential Assembly for additional axle diagnosis. Testing and Inspection
No
GO to E2.
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E2 CHECK TO SEE IF THE ATC SOLENOID IS BEING COMMANDED ON MONITORING FOUR-WHEEL DRIVE (4WD) CLUTCH PWM STATUS (4WDCPWMST) PID
- Ignition OFF.
- Connect: ATC Solenoid C3254.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Monitor the 4WDCPWMST PID.
- Drive the vehicle no faster than 8 km/h (5 mph) in tight turns on dry pavement while monitoring the ATC solenoid duty cycle.
- Is the duty cycle greater than 20%?
Yes
GO to E3.
No
Go To Pinpoint Test F. Pinpoint Test F: DTC P1635 - Tire/Axle Out of Acceptable Range
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E3 CHECK FOR THE CORRECT WHEEL SPEEDS USING THE WHEEL SPEED SENSORS 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 E4.
No
Go To Pinpoint Test F. Pinpoint Test F: DTC P1635 - Tire/Axle Out of Acceptable Range
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E4 CHECK FOR VALID ACCELERATOR PEDAL POSITION MONITORING ACCELERATOR PEDAL POSITION (AP) PID
- Key ON Engine OFF (KOEO).
- Enter the following diagnostic mode on the scan tool: DataLogger - 4X4 Control Module.
- Monitor AP PID while pressing/releasing the accelerator pedal.
- Does the accelerator position match the PID percent value?
Yes
GO to E5.
No
REFER to Computers and Control Systems Information to diagnose the engine control system.
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E5 CHECK FOR CORRECT 4X4 CONTROL MODULE OPERATION
- Disconnect the 4X4 control module.
- Check the harness and component side connectors for:
- corrosion.
- pushed-out/bent pins.
- Check the ATC solenoid jumper harness between the 4X4 control module and the ATC solenoid, located on the rear subframe.
- Connect the 4X4 control module and make sure it seats correctly.
- Operate the system and determine if the concern is still present.
- Is the concern still present?
Yes
INSTALL a new 4X4 control module. REFER to 4X4 Control Module Service and Repair. CLEAR the DTCs. REPEAT the self-test.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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