Symptom Troubleshooting

Symptom Troubleshooting: Poor AM or FM radio reception or interference

Poor AM or FM radio reception or interference

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. Poor reception/interference can be caused by any of these conditions:
- The radio station is far away.

- Atmospheric conditions are unfavorable.

- Aftermarket metallic window tint.

- A tall buildings, mountains, or a high-voltage power lines are nearby.

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

2. Do the seek stop test Sound Quality Diagnosis - Seek Stop Test and the reception level indication in the self-diagnostic function. Initial Inspection and Diagnostic Overview

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 the radio reception/interference is the same in several different locations.

Is the reception/interference the same as a known-good vehicle in several different locations?
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. Remove the rear roof trim. Rear Roof Trim Replacement

7. Wrap aluminum foil (A) around the tip of a tester probe (B) as shown.






8. Touch one tester probe to the antenna element 1P connector No. 1 terminal, and the other tester probe at the antenna element to check for continuity. Replace if there is no continuity.

9. Remove the audio unit. Audio Unit Removal/Installation Check that the AM/FM antenna sub-lead and main-lead are properly connected.

Are they connected properly?
YES - Go to step 10.

NO - Reconnect the connector, and recheck the function.






10. Disconnect the antenna cable 3P connector from the antenna amplifier. Service and Repair

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

12. Turn on the audio unit, and select AM or FM.

13. Measure the voltage between the antenna cable connector terminal No. 3 at the AM/FM antenna amplifier lead and body ground.

Is there battery voltage?
YES - Go to step 19.

NO - Go to step 14.






14. Tune the ignition switch to LOCK (0).

15. Remove the audio unit. Audio Unit Removal/Installation

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

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

17. Check for continuity between audio unit connector D (3P) terminal No. 3 and the AM/FM antenna amplifier 3P connector terminal No. 3.

Is there continuity?
YES - Go to step 18.

NO - Repair open in the wire between the audio unit and the AM/FM antenna amplifier, and check the antenna lead and/or sublead connections.






18. Check for continuity between audio unit connector D (3P) terminal No. 3 and body ground.

Is there continuity?
YES - Repair short to ground in the wire between the audio unit and the AM/FM antenna.

NO - Replace the audio unit. Audio Unit Removal/Installation






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

20. Disconnect audio unit connector E (3P).

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

Is there continuity?
YES - Go to step 22.

NO - Replace the AM/FM antenna lead and/or the sublead.






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

Is there continuity?
YES - Replace the AM/FM antenna lead and/or the sublead.

NO - Go to step 23.






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

Is there continuity?
YES - Go to step 24.

NO - Replace the AM/FM antenna lead and/or the sublead.






24. Check for continuity between audio unit connector D (3P) terminals No. 1 and No. 2.

Is there continuity?
YES - Replace the AM/FM antenna lead and/or the sublead.

NO - Replace the AM/FM antenna amplifier, Service and Repair and recheck. If the reception is still poor, replace the audio unit. Audio Unit Removal/Installation