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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 for aftermarket accessories plugged into the vehicle accessory power sockets.
- Check the connectors for poor connections or loose terminals.
- Check the radio reception in an open area. Compare it to a known-good vehicle whenever possible. Poor reception/interference can be caused by the following:
- The radio station is far away.
- Atmospheric conditions are unfavorable.
- Tall buildings, mountains, or high-voltage power lines are nearby.
- Aftermarket metallic window tinting or electronic accessories.

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. Start the engine.

5. Check the reception/interference.

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 6.

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

7. Check the AM/FM/XM antenna or AM/FM antenna mast for cracks or other damage. Verify that the AM/FM/XM antenna or AM/FM antenna mast is not loose.

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

Is there any damage?

YES -

Replace the AM/FM/XM antenna mast AM/FM/XM Antenna Replacement, or AM/FM antenna mast Service and Repair.�

NO -

Go to step 8.

8. Disconnect the AM/FM/XM antenna or AM/FM antenna 3P connector.

9. Turn the ignition switch to ON (II) and turn on the audio system.

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





Is there battery voltage?

YES -

Go to step 11.

NO -

Go to step 17.

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

12. Remove the audio-navigation unit Audio-Navigation Unit Removal/Installation.

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





Is there continuity?

YES -

Go to step 14.

NO -

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

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





Is there continuity?

YES -

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

NO -

Go to step 15.

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





Is there continuity?

YES -

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

NO -

Go to step 16.

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





Is there continuity?

YES -

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

NO -

Replace the AM/FM/XM antenna or AM/FM antenna Service and Repair, and recheck. If the reception is still poor, replace the audio-navigation unit Audio-Navigation Unit Removal/Installation.�

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

18. Remove the audio-navigation unit Audio-Navigation Unit Removal/Installation.

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





Is there continuity?

YES -

Go to step 20.

NO -

Repair an open in the wire between the audio-navigation unit and the AM/FM/XM antenna or AM/FM antenna.�

20. Check for continuity between AM/FM/XM antenna 3P connector or AM/FM antenna 3P connector 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 the AM/FM/XM antenna or AM/FM antenna.�

NO -

Substitute a known-good audio-navigation unit Audio-Navigation Unit Removal/Installation, and recheck.�