Audio System Symptom Troubleshooting - Poor AM or FM radio reception or interference (without premium audio system)
  1. Check for continuity between the audio unit connector E (3P) terminal No. 3 and body ground.
Is there continuity?
YES -
Repair short to body ground in the wire between the audio unit and AM/FM antenna.■
NO -
Replace the audio unit. ■
  1. Remove the audio unit.
  1. Disconnect audio unit connector E (3P).