A. Symptom Diagnosis

Symptom Diagnosis
Certain circumstances and system limitations will result in occasional vehicle positioning errors. Some customers may think this indicates a problem with the navigation system when, in fact, the system is normal. Keep the "System Limitations" System Limitations items in mind when interviewing customers about navigation system symptoms.

Symptom Duplication

- When the symptom can be duplicated, follow the self-diagnostic procedures (picture diagnosis mode) and the appropriate troubleshooting procedures.
- When the symptom does not reappear or only reappears intermittently, ask the customer about the conditions when the symptom occurred.
- Try to establish if outside interference may have been the cause.
- Try to duplicate the symptom under the same conditions the customer was experiencing.
- Vibration, temperature extremes, and moisture (dew, humidity) are factors that are difficult to duplicate.
- Inspect the vehicle for after-market electronic devices (vehicle locators, amp, etc) that may be hidden.