Inspection and Verification
CAUTION:
Diagnosis by substitution from a donor vehicle is NOT
acceptable. Substitution of control modules does not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle
NOTE:
Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests
- Verify the customer concern
- If a road test is necessary make sure the vehicle is safe to do so
- Visually inspect for obvious signs of mechanical damageVISUAL INSPECTION
Mechanical - Front driveshaft
- Rear driveshaft
- Constant Velocity joint (CV) joints
- Rear driveshaft center support bearing
- Front differential
- Transfer case
- Rear differential
- If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step
- If the cause is not visually evident, verify the symptom and refer to the symptom chart, alternatively check for Diagnostic Trouble Code(s) (DTC)s and refer to the DTC index