Pinpoint Test H: The Vehicle Binds In Turns/Resists Turning/Pulsates/Shudders In A Straight Line
- H1 VERIFY THE CONCERN
- Test drive the vehicle on a straight stretch of road in 4x4 auto mode.
- Drive the vehicle through turns and parking lot maneuvers.
- Does the vehicle bind, pulsate or shudder?
Yes If the problem occurs in A4WD mode, GO to H2; If 4x4 High mode or 4x4 Low mode, binding is a normal condition.
No Go To PINPOINT TEST F .
- H2 CHECK THE 4x4 INDICATORS
- Review the test drive notes.
- Did any of the instrument cluster 4x4 indicators illuminate or flash?
Yes If the 4x4 High or 4x4 Low indicators flashed, GO to H4. If the 4x4 High or 4x4 Low indicators stayed illuminated, GO to H3.
No GO to H5.
- H3 VERIFY THE FAULT
- Review the test drive notes.
- Was 4x4 High or 4x4 Low selected when the 4x4 indicators were illuminated?
Yes The system is functioning correctly.
No The fault may have been caused by an intermittent, uncommanded or autolock shift. TEST the system for normal operation. Go To PINPOINT TEST F .
- H4 CHECK FOR DTCs
- Connect the diagnostic tool.
- Carry out the on-demand self-test.
- Are DTCs retrieved?
Yes REFER to the 4x4 module DTC index for diagnosis.
No GO to H5.
- H5 VERIFY THE CONCERN
- Disconnect: Transfer Case C350.
- Test drive the vehicle on a straight stretch of road and in turns, and shift the transfer case through each mode. Record any fault conditions.
- Is the concern present?
Yes
Vehicles with limited slip rear differential: The condition may be normal and no repair action is necessary. CHECK the rear axle to verify. REFER to DRIVELINE SYSTEM . Vehicles without limited slip rear differential: INSPECT the driveline components for damage or wear. REFER to INSPECTION AND VERIFICATION .
No GO to H6.
- H6 CHECK THE TRANSFER CASE CLUTCH DUTY CYCLE PID
- Connect: Transfer Case C350.
- CLEAR the DTCs.
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Monitor the transfer case clutch duty cycle (pulse width modulated-(PWM)) PID at closed throttle, engine off, key ON.
- Is the clutch duty cycle greater than 10%?
Yes GO to H7.
No CHECK the transfer case. REFER to TRANSFER CASE - ELECTRONIC SHIFT .
- H7 CHECK THE 4WD SHAFT SPEED PIDs
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- While driving the vehicle at 30 km/h (18 mph), monitor the shaft speed PIDs.
- Compare the speedometer reading to the wheel speed PIDs.
- Do the wheel speed PIDs and speedometer speeds match within 1.5 km/h (1 mph)?
Yes GO to H8.
No VERIFY that the four road wheels are the same size and have similar tread depth. CHECK the ABS system for faults. REFER to ANTI-LOCK CONTROL .
- H8 CHECK THE 4WD THROTTLE POSITION PID
- Enter the following diagnostic mode on the diagnostic tool: PID/DATA Monitor and Record.
- Slowly move throttle from closed throttle to WOT and observe the 4WD throttle position PID.
- Does the value vary between 0% at closed throttle and 100% at WOT?
Yes GO to H9.
No CHECK the throttle position sensor and/or PCM for faults. Refer to INTRODUCTION - CNG, FLEX-FUEL & GASOLINE .
- H9 CHECK THE TRANSFER CASE FRONT DRIVESHAFT OUTPUT
- Raise the vehicle on a hoist. For additional information, refer to JACKING & LIFTING .
- Rotate the front driveshaft by hand.
- Does the front driveshaft rotate freely (does it require less than 45 Nm (33 lb-ft) to rotate)?
Yes INSTALL a new 4x4 module. REFER to FOUR-WHEEL DRIVE (4WD) CONTROL MODULE . REPEAT the self-test. TEST the system for normal operation.
No CHECK the transfer case. REFER to TRANSFER CASE - ELECTRONIC SHIFT . TEST the system for normal operation.