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Symptom Troubleshooting




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

Poor AM or FM radio reception or interference (with navigation)

NOTE:

- Check the vehicle battery condition first Testing and Inspection.
- 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.
- Check for aftermarket accessories including cell phones and chargers plugged into the vehicle accessory power sockets.

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

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

Is there any damage?

YES -

Replace the AM/FM/XM antenna mast AM/FM/XM Antenna Replacement (With XM Radio).�

NO -

Go to step 7.

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

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

9. Turn on the audio-navigation unit.

10. Measure the voltage between AM/FM/XM 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. Disconnect audio-navigation unit connector E (3P).

13. Check for continuity between audio-navigation unit connector E (3P) terminal No. 3 and AM/FM/XM antenna 3P connector terminal No. 3.





Is there continuity?

YES -

Go to step 14.

NO -

Repair an open in the wire between the audio-navigation unit and the AM/FM/XM antenna. Also check the AM/FM antenna lead/sublead connector.�

14. Check for continuity between audio-navigation unit connector E (3P) terminal No. 3 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the audio-navigation unit and AM/FM/XM antenna.�

NO -

Replace the audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation).�

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

16. Disconnect audio-navigation unit connector E (3P).

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





Is there continuity?

YES -

Go to step 18.

NO -

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

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





Is there continuity?

YES -

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

NO -

Go to step 19.

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





Is there continuity?

YES -

Go to step 20.

NO -

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

20. Check for continuity between audio-navigation unit connector E (3P) terminals No. 1 and No. 2.





Is there continuity?

YES -

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

NO -

Go to step 21.

21. 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/XM antenna AM/FM/XM Antenna Replacement (With XM Radio), and recheck. If the reception is still poor, replace the audio-navigation unit Audio-Navigation Unit Removal/Installation (With Navigation).�