Audio System Symptom Troubleshooting - Poor or no sound with AM/FM radio

Poor or no sound with AM/FM radio

NOTE:

Check the vehicle 12 volt 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.

Problem verification:

Problem verification

?1.	Park the vehicle in an open area.

?2.	Turn the vehicle to the ON mode.

?3.	Turn on the audio system, and select AM or FM radio station.

Is the sound quality normal?


	YES

Intermittent failure, the system is OK at this time.?


	NO

The failure is duplicated, go to step 2.

Reception/interference check:

Reception/interference check

?1.	Check if the radio reception/interference is the same as the known-good vehicle in several locations.

Is the AM or FM sound quality the same?


	YES

Multipath interference or weak station. Operation is normal.?


	NO

Go to step 3.

Seek stop test:

Seek stop test

?1.	Select the SCAN to check if the number of received radio station are the same as the known-good vehicle.

Are the number of radio station the same?


	YES

Go to step 11.


	NO

Go to step 4.

Determine possible failure area (ANT ?B line, others):

Determine possible failure area (ANT ?B line, others)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Disconnect the following connector.

Roof antenna connector A (3P)

?3.	Turn the vehicle to the ON mode.

?4.

Measure the voltage between test points 1 and 2.

Test condition	Vehicle ON mode
	Roof antenna connector A (3P): disconnected
Test point 1	Roof antenna connector A (3P) (male terminals) No. 1:
Test point 2	Body ground

Is there about 9.0 V?


	YES

The ANT ?B wire is OK. Go to step 7.


	NO

Go to step 5.

Shorted wire check (ANT ?B line):

Shorted wire check (ANT ?B line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Disconnect the following connector.

Tuner unit connector C (5P)

?3.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Roof antenna connector A (3P): disconnected
	Tuner unit connector C (5P): disconnected
Test point 1	Tuner unit connector C (5P) No. 1
Test point 2	Body ground

Is there continuity?


	YES

Repair a short to body ground in the wire.?


	NO

The ANT ?B wire is not shorted to ground. Go to step 6.

Open wire check (ANT ?B line):

Open wire check (ANT ?B line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Roof antenna connector A (3P): disconnected
	Tuner unit connector C (5P): disconnected
Test point 1	Tuner unit connector C (5P) No. 1
Test point 2	Roof antenna connector A (3P) (male terminals) No. 1:

Is there continuity?


	YES

Replace the tuner unit.?


	NO

Repair an open in the wire.?

Shorted wire check (RF IN line):

Shorted wire check (RF IN line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Disconnect the following connector.

Tuner unit connector C (5P)

?3.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Roof antenna connector A (3P): disconnected
	Tuner unit connector C (5P): disconnected
Test point 1	Tuner unit connector C (5P) No. 2
Test point 2	Body ground

Is there continuity?


	YES

There is a short to body ground in the wire. Replace the affected antenna lead.?


	NO

The RF IN wire is not shorted to ground. Go to step 8.

Shorted wire check (RF IN line to SH (RF IN) line):

Shorted wire check (RF IN line to SH (RF IN) line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Roof antenna connector A (3P): disconnected
	Tuner unit connector C (5P): disconnected
Test point 1	Tuner unit connector C (5P) No. 2
Test point 2	Tuner unit connector C (5P) No. 4

Is there continuity?


	YES

There is a short in the wire. Replace the affected antenna lead.?


	NO

The RF IN wire is not shorted to SH(RF IN) wire. Go to step 9.

Open wire check (RF IN line):

Open wire check (RF IN line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Roof antenna connector A (3P): disconnected
	Tuner unit connector C (5P): disconnected
Test point 1	Tuner unit connector C (5P) No. 2
Test point 2	Roof antenna connector A (3P) (male terminals) No. 2:

Is there continuity?


	YES

The RF IN wire is OK. Go to step 10.


	NO

There is an open in the wire. Replace the affected antenna lead.?

10.

Roof antenna check (substitution):

Roof antenna check (substitution)

?1.	Substitute a known-good roof antenna.

?2.	Reconnect all the connectors, and recheck.

Does the symptom go away?


	YES

Replace the original roof antenna.?


	NO

Replace the tuner unit.?

11.

Shorted wire check (SPDIF1 SIG line):

Shorted wire check (SPDIF1 SIG line)

?1.	Turn the vehicle to the OFF (LOCK) mode.

?2.

Disconnect the following connectors.

Audio-navigation unit connector L (2P) (with navigation)

Audio unit connector L (2P) (without navigation)

Tuner unit connector B (2P)

?3.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Audio-navigation unit connector L (2P) (with navigation): disconnected
	Audio unit connector L (2P) (without navigation): disconnected
	Tuner unit connector B (2P): disconnected
Test point 1	Tuner unit connector B (2P) No. 1
Test point 2	Body ground

Is there continuity?


	YES

There is a short to body ground in the wire. Replace the affected shielded harness.?


	NO

The SPDIF1 wire is not shorted to ground. Go to step 12.

12.

Shorted wire check (SPDIF1 SIG line to SPDIF1 SH line):

Shorted wire check (SPDIF1 SIG line to SPDIF1 SH line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Audio-navigation unit connector L (2P) (with navigation): disconnected
	Audio unit connector L (2P) (without navigation): disconnected
	Tuner unit connector B (2P): disconnected
Test point 1	Tuner unit connector B (2P) No. 1
Test point 2	Tuner unit connector B (2P) No. 2

Is there continuity?


	YES

There is a short in the wires. Replace the affected shielded harness.?


	NO

The SPDIF1 SIG and the SPDIF1 SH wires are not shorted. Go to step 13.

13.

Open wire check (SPDIF1 SIG line, SPDIF1 SH line):

Open wire check (SPDIF1 SIG line, SPDIF1 SH line)

?1.

Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	Audio-navigation unit connector L (2P) (with navigation): disconnected
	Audio unit connector L (2P) (without navigation): disconnected
	Tuner unit connector B (2P): disconnected
Test point 1	Audio-navigation unit connector L (2P) (with navigation) No. 1
Test point 1	Audio unit connector L (2P) (without navigation) No. 1
Test point 2	Tuner unit connector B (2P) No. 1

Test point 1	Audio-navigation unit connector L (2P) (with navigation) No. 2
Test point 1	Audio unit connector L (2P) (without navigation) No. 2
Test point 2	Tuner unit connector B (2P) No. 2

Is there continuity?


	YES

The SPDIF1 SIG and the SPDIF1 SH wires are OK. Go to step 14.


	NO

There is an open in the wire(s). Replace the affected shielded harness.?

14.

Tuner unit check (substitution):

Tuner unit check (substitution)

?1.	Substitute a known-good tuner unit.

?2.	Reconnect all the connectors, and recheck.

Does the symptom go away?


	YES

Replace the original tuner unit.?


	NO: With navigation

Replace the audio-navigation unit.?


	NO: Without navigation

Replace the audio unit.?