Poor AM/FM Radio Reception or Interference
Poor AM or FM radio reception or interferenceNOTE:
- Check the vehicle battery condition first.
- Check the radio reception in an open area. Poor reception/interference can be caused by any of these condition:
- The radio station is far away.
- Atmospheric conditions are unfavorable.
- All buildings, mountains, or a high-voltage power lines are nearby.
- Aftermarket window tint.
1. Turn the ignition switch to ON (II).
2. Do the seek stop test.
Is the number of stations the same or 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 - Multi path 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 all of the AM/FM antenna connections and the AM/FM 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. Check the antenna element for cracks, or other damage. Make sure that the AM/FM antenna mast isn't loose and that there is no corrosion on the threads.
NOTE: Do not use any tools to tighten the antenna element.
Is there any damage?
YES - Replace the antenna element.�
NO - Go to step 7.
7. Disconnect the AM/FM antenna sublead 3P connector from the antenna lead.
8. Turn the ignition switch to ON (II).
9. Turn on the audio unit and select AM or FM.
10. Measure the voltage between antenna sublead connector No. 3 terminal and body ground.
Is the battery voltage?
YES - Go to step 14.
NO - Go to step 11.
11. Turn the ignition switch to LOCK (0).
12. Remove the audio unit.
NOTE: Eject the CD before removing the audio unit to prevent damaging the CD player's load mechanism.
13. Check for continuity between audio unit connector C (3P) No. 3 terminal and the AM/FM antenna sublead 3P connector No. 3 terminal.
Is there continuity?
YES - Replace the audio unit.
NO - Replace the AM/FM antenna sublead.
14. Remove the audio unit.
NOTE: Eject the CD before removing the audio unit to prevent damaging the CD player's load mechanism.
15. Check for continuity between audio unit connector C (3P) No. 1 terminal and the AM/FM antenna sublead 3P connector No.1 terminal.
Is there continuity?
YES - Go to step 16.
NO - Replace the AM/FM antenna sublead.
16. Check for continuity between audio unit connector C (3P) No. 1 terminal and body ground.
Is there continuity?
YES - Replace the AM/FM antenna sublead.
NO - Go to step 17.
17. Check for continuity between audio unit connector C (3P) No. 2 terminal and the AM/FM antenna sublead 3P connector No. 2 terminal.
Is there continuity?
YES - Replace the AM/FM antenna sublead.
NO - Go to step 18.
18. Check for continuity between audio unit connector C (3P) No. 1 and No. 2 terminals.
Is there continuity?
YES - Replace the AM/FM antenna sublead.
NO - Go to step 19.
19. Verify the AM/FM antenna mounting nut torque.
Is the AM/FM antenna mounting nut tight?
YES - Go to step 20.
NO - Retorque and recheck reception.
20. Substitute a known-good AM/FM antenna lead/amplifier and check the reception/interference.
Is the reception/interference still poor?
YES - Go to step 21.
NO - Replace the AM/FM antenna lead/amplifier.
21. Substitute a known-good AM/FM antenna and check the reception/interference.
Is the reception/interference still poor?
YES - Replace the audio unit.
NO - Replace the AM/FM antenna.