Symptom Duplication

• When the symptom can be duplicated, verify that it is not a characteristic of the system. Review the navigation system manual and compare it to a known-good vehicle (with the same software and database), under the same conditions. If the symptom is not the same, as the known-good follow the self-diagnostic procedures and the appropriate troubleshooting procedures.
• 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 (vehicle locators, amps, radar detectors, etc.) that may be hidden.

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 DVDs or other system components can delay the troubleshooting process by causing side effects unrelated to the original problem.