When the symptom does not reappear or only reappears intermittently, ask the client about the conditions when the symptom occurred.
- Always ask the client to demonstrate the problem
- Try to establish possible user error or misunderstanding of the system
- Try to establish if outside interference may have been the cause
- Try to duplication the symptom under the same conditions the client experienced
- Vibration, temperature extremes, and moisture (dew, humidity) are factors that are difficult to duplicate
- Inspect the vehicle for after-market electronic devices (amp, CD players/changers, radar detectors, theft recovery systems, etc.) that may be hidden
NOTE:
When troubleshooting navigation system problems, ensure that the known-good vehicle is the same software version year and model as the vehicle being serviced. Mixing incompatible navigation systems or other system components can delay the troubleshooting process by creating symptoms or issues unrelated to the original problem.