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 conditions:
- The radio station is far away.
- Atmospheric conditions are unfavorable.
- A tall buildings, mountains, or a high-voltage power lines are nearby.
- Aftermarket window tint.
1. Turn the ignition switch ON (II).
2. Do the seek stop test.
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 if the radio reception/interference is the same in several locations.
Is the reception/interference the same?
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. Tune the ignition switch OFF.
6. Remove the rear roof trim.
7. 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.
8. Remove the audio unit. Check that the AM/FM antenna sub-lead and main-lead are properly connected.
Are they connected properly?
YES - Go to step 9.
NO - Reconnect the connector, and recheck the function.
9. Disconnect the antenna cable 3P connector from the antenna amplifier.
10. Tune the ignition switch ON (II).
11. Turn on the audio unit and select AM or FM.
12. Measure the voltage between the antenna cable connector No. 3 terminal at the AM/FM antenna AMPLIFIER lead and body ground.
Is there battery voltage?
YES - Go to step 17.
NO - Go to step 13.
13. Tune the ignition switch OFF.
14. Disconnect the 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.
15. Check for continuity between the audio unit connector E (3P) No. 3 terminal and the AM/FM antenna amplifier 3P connector No. 3 terminal.
Is there continuity?
YES - Go to step 16.
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.
16. Check for continuity between audio unit connector E (3P) No. 3 terminal and body ground.
Is there continuity?
YES - Repair short to ground in the wire between the audio unit and AM/FM antenna.
NO - Replace the audio unit.
17. Tune the ignition switch OFF.
18. Disconnect the 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.
19. Check for continuity between the audio unit connector E (3P) No. 1 terminal and the AM/FM antenna amplifier 3P connector No. 1 terminal.
Is there continuity?
YES - Go to step 20.
NO - Replace the AM/FM antenna lead and/or sublead.
20. Check for continuity between the audio unit connector E (3P) No. 1 terminal and body ground.
Is there continuity?
YES - Replace the AM/FM antenna lead and/or sublead.
NO - Go to step 21.
21. Check for continuity between the audio unit connector E (3P) No. 2 terminal and the AM/FM antenna amplifier 3P connector No. 2 terminal.
Is there continuity?
YES - Go to step 22.
NO - Replace the AM/FM antenna lead and/or sublead.
22. Check for continuity between the audio unit connector E (3P) No. 1 and No. 2 terminals.
Is there continuity?
YES - Replace the AM/FM antenna lead and/or sublead.
NO - Replace the AM/FM antenna amplifier, and recheck. If the reception is still poor, replace the audio unit.