Inspection and Verification (Start Testing Here)

1. Verify the customer concern by operating the vehicle to duplicate the condition.
2. Visually inspect the vehicle to determine any obvious cause(s) of the concern(s).
3. If the inspection reveals obvious causes that can be readily identified, repair as necessary.
4. If the concern(s) remains after the inspection, determine the symptom(s) and go to the Symptom Chart. Symptom Related Diagnostic Procedures

How To Use This Diagnostic Procedure Section
- Noise, Vibration and Harshness (NVH) concerns have become more important as vehicles have become more sensitive to these vibrations. This is designed to aid in identifying these situations.
- The diagnostic procedures are provided based on symptom. If the condition occurs at high speed, for instance, the most likely place to start is under High Speed Shake.
- The road test procedure will tell how to sort the conditions into categories and how to tell a vibration from a shake.
- A series of Road Test Quick Checks is provided to make sure that a cause is either pinpointed or eliminated.
- Name the condition, proceed to the appropriate system/ component and locate the correct diagnosis. When the condition is identified, the job is partly done.
- Follow the diagnostic procedure.
- Quick Checks are described within the step, while more involved tests and adjustments are in General Procedures.
- Always follow each step exactly and make notes to recall important findings later.