Inspection and Verification (Start Testing Here)

1. Verify the customer's concern by operating the vehicle to duplicate the condition.
2. Visually inspect the vehicle to determine any obvious causes of the concern(s).
3. If the inspection reveals obvious concern(s) that can be readily identified, service as required.
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 concerns have become more important as vehicles have become more sensitive to these conditions. This section is designed to aid in identifying these situations.
- The section provides diagnostic procedures 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 out 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.
- Use Vehicle Road Test Evaluation Form to record road test results.
- Use the Glossary to become familiar with the terms.
- Name the condition, go to the appropriate section and locate the proper diagnosis. When the condition is identified, the job is partly done.
- Follow the diagnostic procedure.
- Follow the steps within the section.
- Quick Checks are described within the step, while more involved tests and adjustments are found in Service Procedures and Adjustments.
- Always follow each step exactly and make notes along the way to recall important findings later.

Customer Interview
The road test and customer interview (if available) provide information that will help identify the concern and will provide direction to the correct starting point for diagnosis.
- Use Customer Concern Evaluation Form to record customer concerns.