Symptom Troubleshooting
Audio System Symptom Troubleshooting - Poor AM or FM radio reception or interference (without navigation)
Poor AM or FM radio reception or interference (without navigation)
NOTE:
- Check the vehicle battery condition first. Testing and Inspection
- Check the radio reception in an open area.
- Compare it to a known-good vehicle of the same model, year, and trim level whenever possible.
- If necessary, have the customer demonstrate the symptom.
- Poor reception/interference can be caused by following:
- The radio station is far away.
- Atmospheric conditions are unfavorable.
- Tall buildings, mountains, or high-voltage power lines are nearby.
- Electronic accessories.
- Non-standard antenna mast.
- Check for aftermarket accessories plugged into the vehicle accessory power sockets (including cell phones).
- Check the connectors for poor connections or loose terminals.
1. Turn the ignition switch to ON (II).
2. Do the seek stop test Audio System Sound Quality Diagnosis.
Does the test vehicle receive 90 % of the same stations as the known-good vehicle?
YES -
Multipath interference or weak station. Operation is normal at this time.�
NO -
Go to step 3.
3. Check if the radio reception/interference is the same as the known-good vehicle in several locations.
Is the reception/interference the same as the known-good vehicle in several different locations?
YES -
Multipath interference or weak station. Operation is normal.�
NO -
Go to step 4.
4. Check the reception/interference while the engine is running, and compare it to the known-good vehicle.
Is there noise (static or whine) only with the engine running?
YES -
Check the antenna and radio grounds. If OK, check the charging system, the fuel injection system (fuel pump), the HVAC blower motor, and the ignition system.�
NO -
Go to step 5.
5. Turn the ignition switch to LOCK (0).
6. Check the antenna mast for cracks or other damage. Make sure that the AM/FM antenna is not loose.
NOTE: Do not use any tools to tighten the antenna mast.
Is there any damage?
YES -
Replace the AM/FM antenna Service and Repair.�
NO -
Go to step 7.
7. Disconnect the antenna cable 3P connector from the AM/FM antenna Service and Repair.
8. Turn the ignition switch to ON (II).
9. Measure the voltage between antenna cable connector terminal No. 3 at the antenna amplifier lead and body ground.
Is there battery voltage?
YES -
Go to step 15.
NO -
Go to step 10.
10. Turn the ignition switch to LOCK (0).
11. Remove the audio unit Audio Unit Removal/Installation (Without Navigation).
12. Disconnect audio unit connector G (3P).
13. Check for continuity between audio unit connector G (3P) terminal No. 3 and antenna amplifier 3P connector terminal No. 3.
Is there continuity?
YES -
Go to step 14.
NO -
Repair an open in the wire between the audio unit and the antenna amplifier.�
14. Check for continuity between antenna amplifier connector (3P) terminal No. 3 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the audio unit and the antenna amplifier.�
NO -
Substitute a known-good audio unit, and recheck.�
15. Remove the audio unit Audio Unit Removal/Installation (Without Navigation).
16. Check for continuity between audio unit connector G (3P) terminal No. 1 and antenna amplifier 3P connector terminal No. 1.
Is there continuity?
YES -
Go to step 17.
NO -
Replace the antenna lead and/or the sublead.�
17. Check for continuity between audio unit connector G (3P) terminal No. 1 and body ground.
Is there continuity?
YES -
Replace the antenna lead and/or the sublead.�
NO -
Go to step 18.
18. Check for continuity between audio unit connector G (3P) terminal No. 2 and antenna amplifier 3P connector terminal No. 2.
Is there continuity?
YES -
Replace the antenna lead and/or the sublead.�
NO -
Go to step 19.
19. Check for continuity between audio unit connector G (3P) terminals No. 1 and No. 2.
Is there continuity?
YES -
Replace the antenna lead and/or the sublead.�
NO -
Replace the antenna amplifier, and recheck. If the reception is still poor, replace the audio unit Audio Unit Removal/Installation (Without Navigation).�