Operation CHARM: Car repair manuals for everyone.
Hosted by mcallihan.com

Symptom Troubleshooting




Audio System Symptom Troubleshooting - Poor AM or FM radio reception or interference

Poor AM or FM radio reception or interference (with navigation, USA models)

NOTE:

- Check the vehicle battery condition first 12 Volt Battery Test.
- Check for aftermarket accessories including cell phones and chargers plugged into the vehicle accessory power sockets.
- Check the radio reception in an open area. Poor reception/interference can be caused by the following:
- The radio station is far away.
- A tall building, a mountain, or a high-voltage power line is nearby.
- Aftermarket window tint.

1. Turn the ignition switch to ON (II).

2. Do the seek stop test.

Is the test vehicle within 10 % of the known-good vehicle?

YES -

Multipath interference or weak station. Operation is normal.

NO -

Go to step 3.

3. Check if the radio reception/interference is the same in several locations.

Is the reception/interference the same?

YES -

Go to step 4.

NO -

Multipath interference or weak station. Operation is normal.

4. Check the reception/interference while the engine is running.

Is there noise (static or whine) only with the engine running?

YES -

Check the antenna and radio grounds. If OK, check the charging system and the ignition system.

NO -

Go to step 5.

5. Turn the ignition switch to LOCK (0).

6. Check the AM/FM antenna mast for cracks, or other damage. Make sure that the AM/FM antenna mast isn't loose.

NOTE: Do not use any tools to tighten the AM/FM antenna mast.

Is there any damage?

YES -

Replace the AM/FM antenna mast.

NO -

Go to step 7.

7. Disconnect the AM/FM antenna 3P connector from the AM/FM antenna.

8. Turn the ignition switch to ON (II).

9. Turn on the audio-navigation unit.

10. Measure the voltage between AM/FM antenna 3P connector terminal No. 3 and body ground.





Is there battery voltage?

YES -

Go to step 15.

NO -

Go to step 11.

11. Turn the ignition switch to LOCK (0).

12. Remove the audio-navigation unit Audio-Navigation Unit Removal/Installation, and disconnect the FM distributor 3P connector.

13. Check for continuity between FM distributor 3P connector terminal No. 3 and AM/FM antenna 3P connector terminal No. 3.





Is there continuity?

YES -

Go to step 14.

NO -

Repair an open in the wire between the FM distributor and the AM/FM antenna. Also check the AM/FM antenna lead/sublead connector.

14. Check for continuity between FM distributor 3P connector terminal No. 3 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the FM distributor and the AM/FM antenna.

NO -

Substitute a known-good FM distributor FM Distributor Removal/Installation, and recheck. If the reception is still poor, replace the audio-navigation unit Audio-Navigation Unit Removal/Installation.

15. Turn the ignition switch to LOCK (0).

16. Remove the audio-navigation unit Audio-Navigation Unit Removal/Installation, and disconnect audio-navigation unit connector G (3P).

17. Check for continuity between audio-navigation unit connector G (3P) terminal No. 1 and AM/FM antenna 3P connector terminal No. 1.





Is there continuity?

YES -

Go to step 20.

NO -

Go to step 18.

18. Disconnect the FM distributor 3P connector.

19. Check for continuity between FM distributor 3P connector terminal No. 1 and AM/FM antenna 3P connector terminal No. 1.





Is there continuity?

YES -

Replace the FM distributor FM Distributor Removal/Installation.

NO -

Replace the AM/FM antenna lead and/or sublead.

20. Check for continuity between audio-navigation unit connector G (3P) terminal No. 1 and body ground.





Is there continuity?

YES -

Go to step 21.

NO -

Go to step 23.

21. Disconnect the FM distributor 3P connector.

22. Check for continuity between FM distributor 3P connector terminal No. 1 and body ground.





Is there continuity?

YES -

Replace the AM/FM antenna lead and/or sublead.

NO -

Replace the FM distributor FM Distributor Removal/Installation.

23. Check for continuity between audio-navigation unit connector G (3P) terminal No. 2 and AM/FM antenna 3P connector terminal No. 2.





Is there continuity?

YES -

Go to step 26.

NO -

Go to step 24.

24. Disconnect the FM distributor 3P connector.

25. Check for continuity between FM distributor 3P connector terminal No. 2 and AM/FM antenna 3P connector terminal No. 2.





Is there continuity?

YES -

Replace the FM distributor FM Distributor Removal/Installation.

NO -

Replace the AM/FM antenna lead and/or sublead.

26. Check for continuity between audio-navigation unit connector G (3P) terminal No. 1 and No. 2.





Is there continuity?

YES -

Go to step 27.

NO -

Go to step 29.

27. Disconnect the FM distributor 3P connector.

28. Check for continuity between FM distributor 3P connector terminal No. 1 and No. 2.





Is there continuity?

YES -

Replace the AM/FM antenna lead and/or sublead.

NO -

Replace the FM distributor FM Distributor Removal/Installation.

29. Substitute a known-good AM/FM antenna lead and/ or sublead, and check the radio reception.

Is the reception normal?

YES -

Replace the AM/FM antenna lead and/or sublead.

NO -

Substitute a known-good AM/FM antenna, and recheck. If the reception is still poor, replace the audio-navigation unit.