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 connectors for poor connections or loose terminals.
- 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 any of these conditions:
- The radio station is far away.
- Atmospheric conditions are unfavorable.
- Tall buildings, mountains, or high-voltage power lines are nearby.
- Aftermarket window tinting or electronic accessories.
- Non-standard antenna mast.
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 that the radio reception/interference is the same as the known-good vehicle in several 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 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, fuel injection system (fuel pump), HVAC (blower motor), and the ignition system.�
NO -
Go to step 5.
5. Turn the ignition switch to LOCK (0).
6. Check the AM/FM antenna or AM/FM/XM antenna mast for cracks, or other damage. Make sure that the AM/FM antenna or AM/FM/XM antenna is not loose.
NOTE: Do not use any tools to tighten the AM/FM antenna or AM/FM/XM antenna mast.
Is there any damage?
YES -
Replace the AM/FM antenna AM/FM Antenna Replacement (Without XM Radio) or AM/FM/XM antenna AM/FM/XM Antenna Replacement (With XM Radio).�
NO -
Go to step 7.
7. Disconnect the AM/FM antenna 3P connector .
8. Turn the ignition switch to ON (II).
9. Turn on the audio unit.
10. Measure the voltage between the AM/FM antenna 3P connector terminal No. 3 and body ground.
Is there battery voltage?
YES -
Go to step 16.
NO -
Go to step 11.
11. Turn the ignition switch to LOCK (0).
12. Remove the audio unit Audio Unit Removal/Installation.
13. Disconnect audio unit connector G (3P).
14. 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 15.
NO -
There is 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 the AM/FM antenna 3P connector terminal No. 3 and body ground.
Is there continuity?
YES -
Repair a short in the wire between the audio unit and the AM/FM antenna.�
NO -
Substitute a known-good audio unit Audio Unit Removal/Installation, and recheck.�
16. Remove the audio unit Audio Unit Removal/Installation.
17. 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 18.
NO -
Replace the AM/FM antenna lead and/or sublead.�
18. Check for continuity between audio 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 19.
19. 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 20.
NO -
Replace the AM/FM antenna lead and/or sublead.�
20. Check for continuity between audio unit connector G (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 antenna AM/FM Antenna Replacement (Without XM Radio) or AM/FM/XM antenna (with XM radio) AM/FM/XM Antenna Replacement (With XM Radio), and recheck. If the reception is still poor, replace the audio unit Audio Unit Removal/Installation.�