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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 (without navigation)

NOTE:

- Check the vehicle battery condition first.
- Check the connectors for poor connections or loose terminals.
- 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. Do the seek stop test, and check the radio reception/interference.

Is the reception/interference OK?

YES -

Multipath interference or weak station. Operation is normal.

NO -

Go to step 2.

2. With the help of an assistant inside the vehicle, have the assistant shine a strong flashlight (A) along each rear antenna ground wire (B). Check from the outside of the vehicle for any breaks or openings in the rear antenna ground wires (the light shines through any breaks or cuts).

NOTE: It is easier to see the breaks if you do this test in a dark or shaded area.





Are there any breaks or cuts in the rear antenna ground?

YES -

Repair the rear antenna ground. Go to window grid repair Window Grid Repair, or replace the rear window Upper Rear Window Replacement if the damaged section is too long.

NO -

Go to step 3.

3. Disconnect the rear antenna ground 1P connector.

4. Check for continuity between rear antenna ground 1P connector terminal No. 1 and body ground.





Is there continuity?

YES -

Go to step 5.

NO -

Repair an open or high resistance in the wire between the rear antenna ground 1P connector terminal No. 1 and body ground (G801).

5. 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 6.

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

7. Check the AM/FM antenna for cracks or other damage.

Is there any damage?

YES -

Replace the AM/FM antenna.

NO -

Go to step 8.

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

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

10. Turn on the audio unit.

11. Measure the voltage between AM/FM antenna 3P connector terminal No. 1 and body ground.





Is there battery voltage?

YES -

Go to step 16.

NO -

Go to step 12.

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

13. Remove the audio unit Audio Unit Removal / Installation, and disconnect audio unit connector G (3P).

NOTE: Eject all the discs before removing the audio unit to prevent damaging the CD player's load mechanism.

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





Is there continuity?

YES -

Go to step 15.

NO -

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

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





Is there continuity?

YES -

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

NO -

Replace the audio unit.

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

17. Remove the audio unit Audio Unit Removal / Installation, and disconnect audio unit connector G (3P).

NOTE: Eject all the discs before removing the audio unit to prevent damaging the CD player's load mechanism.

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





Is there continuity?

YES -

Go to step 19.

NO -

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

19. Check for continuity between audio unit connector G (3P) terminal No. 2 and body ground.





Is there continuity?

YES -

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

NO -

Go to step 20.

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





Is there continuity?

YES -

Go to step 21.

NO -

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

21. Check for continuity between audio unit connector G (3P) terminals No. 2 and No. 3.





Is there continuity?

YES -

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

NO -

Go to step 22.

22. 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 unit.