Audio System Symptom Troubleshooting - Poor AM or FM radio reception or interference
Poor AM or FM radio reception or interference
NOTE:
Check the vehicle battery condition first.
Check for aftermarket accessories plugged into the vehicle accessory power sockets.
Check for any radio frequency modulators that are plugged into the FM antenna lead. These modulators allow customers to play audio from accessories like CD players or game consoles using the audio system, but they can create interference issues.
Check the radio reception in an open area. Compare it to a known-good vehicle whenever possible. Poor reception/interference can be caused by the following:
?
The radio station is far away
?
Atmospheric conditions are unfavorable
?
Tall buildings, mountains, or high-voltage power lines are nearby
?
Electrical loads like the rear window defroster, seat heaters, game consoles, etc.
Check the connectors for poor connections or loose terminals.

1.
Problem verification:

Problem verification
?1.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?2.
Do the Seek Stop Test in the Sound Quality Diagnosis.

Is the test vehicle within 10 % of the known-good vehicle?

     
YES
     
     
     
Multipath interference or weak station. Operation is normal.?
     
NO
     
     
     
The failure is duplicated, go to step 2.
2.
Determine possible failure area (charging system and ignition system, others):

Determine possible failure area (charging system and ignition system, others)
?1.
Start the engine, and turn on the electrical loads one at a time (defrosters, seat heaters, blower motor, etc.).

?2.
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 3.
3.
Window antenna check:

Window antenna check
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
With the help of an assistant inside the vehicle, have the assistant shine a strong flashlight (A) along each antenna wire (B). Check from the outside of the vehicle for any breaks or openings in the antenna wires (the light shines through any breaks or cuts).
NOTE: It is easier to see the breaks if you do this test in a dark or shaded area.


Are there any breaks or cuts in the antenna wire?

     
YES
     
     
     
Repair the window antenna. Go to window antenna repair, or replace the rear window if the damaged section is too long.?
     
NO
     
     
     
Go to step 4.
4.
Determine possible failure area (SWD +B line, AM/FM line):

Determine possible failure area (SWD+B line, AM/FM line)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

?4.
Turn on the audio unit.

?5.
Measure the voltage between test points 1 and 2.
Test condition
IG ON (II) or ON mode
 
AM/FM antenna amplifier 3P connector: disconnected
Test circuit
SWD +B
Test point 1
AM/FM antenna amplifier 3P connector No. 1
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
The SWD +B wire is OK. Go to step 5.
     
NO
     
     
     
Go to step 10.
5.
Open wire check (AM/FM line):

Open wire check (AM/FM line)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
AM/FM
Test point 1
Audio unit connector L (3P) No. 2
Test point 2
AM/FM antenna amplifier 3P connector No. 2


Is there continuity?

     
YES
     
     
     
The AM/FM wire is not open. Go to step 6.
     
NO
     
     
     
Replace the AM/FM antenna lead and/or the sublead.?
6.
Shorted wire check (AM/FM line):

Shorted wire check (AM/FM line)
?1.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
AM/FM
Test point 1
Audio unit connector L (3P) No. 2
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Replace the AM/FM antenna lead and/or the sublead.?
     
NO
     
     
     
The AM/FM wire is not shorted to ground. Go to step 7.
7.
Open wire check (SH (AM/FM) line):

Open wire check (SH (AM/FM) line)
?1.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
SH (AM/FM)
Test point 1
Audio unit connector L (3P) No. 3
Test point 2
AM/FM antenna amplifier 3P connector No. 3


Is there continuity?

     
YES
     
     
     
The SH (AM/FM) wire is not open. Go to step 8.
     
NO
     
     
     
Replace the AM/FM antenna lead and/or the sublead.?
8.
Shorted wire check (AM/FM line to SH (AM/FM) line):

Shorted wire check (AM/FM line to SH (AM/FM) line)
?1.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
AM/FM, SH (AM/FM)
Test point 1
Audio unit connector L (3P) No. 2
Test point 2
Audio unit connector L (3P) No. 3


Is there continuity?

     
YES
     
     
     
Replace the AM/FM antenna lead and/or the sublead.?
     
NO
     
     
     
The AM/FM antenna lead is OK. Go to step 9.
9.
AM/FM antenna amplifier check (substitution):

AM/FM antenna amplifier check (substitution)
?1.
Substitute a known-good AM/FM antenna amplifier.

?2.
Reconnect all the connectors, and recheck.

Does the symptom go away?

     
YES
     
     
     
Replace the original AM/FM antenna amplifier.?
     
NO
     
     
     
10.
Open wire check (SWD +B line):

Open wire check (SWD +B line)
?1.
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
SWD +B
Test point 1
Audio unit connector L (3P) No. 1
Test point 2
AM/FM antenna amplifier 3P connector No. 1


Is there continuity?

     
YES
     
     
     
The SWD +B wire is not open. Go to step 11.
     
NO
     
     
     
Repair an open in the wire between the audio unit and the AM/FM antenna amplifier.?
11.
Shorted wire check (SWD +B line):

Shorted wire check (SWD +B line)
?1.
Check for continuity between test points 1 and 2.
Test condition
IG LOCK (0) or OFF mode
 
AM/FM antenna amplifier 3P connector: disconnected
 
Audio unit connector L (3P): disconnected
Test circuit
SWD +B
Test point 1
AM/FM antenna amplifier 3P connector No. 1
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short to body ground in the wire between the audio unit and the AM/FM antenna amplifier.?
     
NO