Inspection and Verification (Start Testing Here)

Noise, Vibration, and Harshness (NVH) is becoming more important because vehicles are becoming more sensitive to vibrations. This outlines the process of diagnosing NVH situations. An accurate description of the symptom is necessary to proceed with proper diagnosis.

The Road Test will tell how to sort conditions into the proper symptom to better identify the concern. It will give hints on quick checks to make sure that a condition is either pinpointed or eliminated.

How to Use This Diagnostic Procedure

Road Test Form:

Road Test Form (continued):

The first step is to fill out the NVH Worksheet/Road Test Form to obtain all necessary information from the customer. After the road test form is filled out the next step is to perform a Road Test. The combination of filling out the road test form and performing the actual road test will help you name the symptom. Next you will proceed to the Symptom Chart. The Symptom Chart will tell you where to go to find the diagnostic information necessary to repair the symptom. Symptom Related Diagnostic Procedures

Customer Interview
It is important to interview the customer. Customer feedback can supply information that could be helpful in diagnosing the concern. Ask questions like:
- When is the concern present (at idle or while driving)?
- Where does the concern appear to be coming from?
- How long has the concern been there? Has it steadily become worse?
- When did the concern start?