How to Use The Diagnostic Procedure

- Noise, vibration and harshness concerns have become more important as vehicles have become more sensitive to these vibrations. This is designed to aid in identifying these situations.
- This 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 system and locate the proper diagnosis. When the condition is identified, the job is partly done.
- Follow the diagnostic procedure.
- Follow the steps within.
- Quick Checks are 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.