Poor AM Or FM Radio Reception Or Interference (Without Navigation With XM)
- Check the vehicle battery condition first (see BATTERY TEST ).
- Check the radio reception in an open area. Poor reception/interference can be caused by the following:
- The radio station is far away.
- A tall building, a mountain, or a high-voltage power line is nearby.
- Aftermarket window tint.
- Check for aftermarket accessories including cell phones and chargers plugged into the vehicle accessory power sockets.
- Turn the ignition switch to ON (II).
- Do 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.
- 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.
- Check the reception/interference while the engine is running.
Is there noise 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.
- Turn the ignition switch to LOCK (0).
- Check the AM/FM/XM antenna mast for cracks, or other damage. Make sure that the AM/FM/XM antenna mast isn't loose.NOTE: Do not use any tools to tighten the AM/FM/XM antenna mast.
Is there any damage?
YES - Replace the AM/FM/XM antenna mast (see AM/FM/XM ANTENNA REPLACEMENT ).
NO - Go to step 7.
- Disconnect the AM/FM antenna 1P connector from the AM/FM antenna.
- Turn the ignition switch to ON (II).
- Turn on the audio unit.
- Measure the voltage between AM/FM/XM antenna 3P connector terminal No. 3 and body ground.
Is there battery voltage?
YES - Go to step 15.
NO - Go to step 11.
- Turn the ignition switch to LOCK (0).
- Disconnect audio unit connector E (3P).
- Check for continuity between audio unit connector E (3P) terminal No. 3 and AM/FM/XM antenna 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 AM/FM/XM antenna. Also check the AM/FM antenna lead/sublead connector.
- Check for continuity between audio unit connector E (3P) terminal No. 3 and body ground.
Is there continuity?
YES - Repair short to body ground in the wire between the audio unit and AM/FM antenna.
NO - Replace the audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ).
- Turn the ignition switch to LOCK (0).
- Disconnect audio unit connector E (3P).
- Check for continuity between audio unit connector E (3P) terminal No. 1 and AM/FM/XM antenna 3P connector terminal No. 1.
Is there continuity?
YES - Go to step 18.
NO - Replace the AM/FM antenna lead and/or sublead.
- Check for continuity between audio unit connector E (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.
- Check for continuity between audio unit connector E (3P) terminal No. 2 and AM/FM/XM antenna 3P connector terminal No. 2.
Is there continuity?
YES - Go to step 20.
NO - Replace the AM/FM antenna lead and/or sublead.
- Check for continuity between audio unit connector E (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.
- Substitute a known-good AM/FM antenna lead and/or sublead, and check the radio operation.
Is the reception normal?
YES - Replace the AM/FM antenna lead and/or sublead.
NO - Substitute a known-good AM/FM/XM antenna (see AM/FM/XM ANTENNA REPLACEMENT ) and recheck. If the reception is still poor, replace the audio unit (see AUDIO UNIT REMOVAL/INSTALLATION ).