Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Audio system sound is weak or distorted (display is normal) (Without Navigation, With ELS Audio)
NOTE:
- Check the vehicle battery condition first .
- Set the fader and the balance positions to the center.
- Check the connectors for poor connections or loose terminals.
- Problem verification
-1. Turn on the audio system, and check for sound in each mode (AM/FM, XM, AUX, USB, Bluetooth audio, and CD).
Is the sound weak or distorted in each mode?
YES: Sound is weak or distorted in all modes
The failure is duplicated, go to step 2.
YES: Sound is weak or distorted in AM/FM mode
Go to AM/FM radio display is blank or no station information is displayed troubleshooting .
YES: Sound is weak or distorted in XM mode
Go to Poor or no sound with XM radio (Audio unit does display XM channels) troubleshooting .
YES: Sound is weak or distorted in AUX mode
Go to Auxiliary input sound is low or cannot be heard troubleshooting .
YES: Sound is weak or distorted in USB mode
Go to USB input sound is low or cannot be heard troubleshooting .
YES: Sound is weak or distorted in Bluetooth audio mode
Go to No sound when Bluetooth audio is used troubleshooting .
YES: Sound is weak or distorted in CD mode
Go to Audio disc does not play troubleshooting .
NO
Intermittent failure, the system is OK at this time.
- Speaker output check 1
-1. Go into the System Diagnostic Mode, and use the speaker check mode .
Did all check mode (FL, FR, RR, RL) produce a tone?
YES
Go to step 3.
NO
Go to step 4.
- Speaker output check 2
-1. Go into the System Diagnostic Mode, and use the speaker check mode .
Did all speakers produce a tone?
YES
Go to step 7.
NO: Sound is low or cannot be heard in front door tweeter (s)
Go to step 11.
NO: Sound is low or cannot be heard in some speaker except front door tweeter (s)
Go to step 14.
- Shorted wire check (PRE lines)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connectors.
NOTE: Eject the disc before disconnecting the audio unit to prevent damaging the CD/DVD player's load mechanism.
Stereo amplifier connector B (28P) Audio unit connector A (24P) -3. Check for continuity between these test points and body ground individually.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Connector Test circuits Terminal Audio unit connector A (24P) FL PRE+ No. 15 (BLK) FL PRE- No. 16 (GRN) FR PRE+ No. 19 (WHT) FR PRE- No. 20 (RED) Is there continuity?
YES
There is a short to body ground in the wires between the audio unit and the stereo amplifier. Replace the affected shielded harness.
NO
The PRE wires are not shorted to ground. Go to step 5.
- Shorted wire check (PRE+ lines to PRE- lines)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Test circuits Connector: Audio unit connector A (24P) Test point 1 Test points 2 FL PRE+ to FL PRE- No. 15 (BLK) No. 16 (GRN) FR PRE+ to FR PRE- No. 19 (WHT) No. 20 (RED) Is there continuity?
YES
There is a short in the wires between the audio unit and the stereo amplifier. Replace the affected shielded harness.
NO
The PRE+and the PRE- wires are not shorted. Go to step 6.
- Open wire check (PRE lines)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Test circuits Test point 1:Audio unit connector A (24P) Test point 2:Stereo amplifier connector B (28P) FL PRE+ No. 15 (BLK) No. 9 (BLK) FL PRE- No. 16 (GRN) No. 23 (GRN) FR PRE+ No. 19 (WHT) No. 8 (WHT) FR PRE- No. 20 (RED) No. 22 (RED) Is there continuity
YES
The PRE wires are OK. Go to step 10.
NO
There is an open in the wire (s) between the audio unit and the stereo amplifier. Replace the affected shielded harness.
- Shorted wire check (PRE lines)
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Disconnect the following connectors.
NOTE: Eject the disc before disconnecting the audio unit to prevent damaging the CD/DVD player's load mechanism.
Stereo amplifier connector B (28P) Audio unit connector A (24P) Audio unit connector B (8P) -3. Check for continuity between these test points and body ground individually.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Audio unit connector B (8P): disconnected Connector Test circuits Terminal Audio unit connector A (24P) RL PRE+ No. 5 (BLU) RL PRE- No. 6 (RED) RR PRE+ No. 9 (BLK) RR PRE- No. 10 (WHT) Connector Test circuits Terminal Audio unit connector B (8P) CTR PRE+ No. 1 (PNK) CTR PRE- No. 3 (LT GRN) SUB W PRE+ No. 5 (LT BLU) SUB W PRE- No. 7 (ORN) Is there continuity?
YES
There is a short to body ground in the wire (s) between the audio unit and the stereo amplifier. Replace the affected shielded harness.
NO
The PRE wires are not shorted to ground. Go to step 8.
- Shorted wire check (PRE+ lines to PRE- lines)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Audio unit connector B (8P): disconnected Test circuits Connector: Audio unit connector A (24P) Test point 1 Test points 2 RL PRE+ to RL PRE- No. 5 (BLU) No. 6 (RED) RR PRE+ to RR PRE- No. 9 (BLK) No. 10 (WHT) Test circuits Connector: Audio unit connector B (8P) Test point 1 Test points 2 CTR PRE+ to CTR PRE- No. 1 (PNK) No. 3 (LT GRN) SUB W PRE+ to SUB W PRE- No. 5 (LT BLU) No. 7 (ORN) Is there continuity?
YES
There is a short in the wires between the audio unit and the stereo amplifier. Replace the affected shielded harness.
NO
The PRE+and the PRE- wires are not shorted. Go to step 9.
- Open wire check (PRE lines)
-1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector B (28P): disconnected Audio unit connector A (24P): disconnected Audio unit connector B (8P): disconnected Test circuits Test point 1:Audio unit connector A (24P) Test point 2:Stereo amplifier connector B (28P) RL PRE+ No. 5 (BLU) No. 7 (BLU) RL PRE- No. 6 (RED) No. 21 (RED) RR PRE+ No. 9 (BLK) No. 6 (BLK) Test circuits Test point 1:Audio unit connector A (24P) Test point 2:Stereo amplifier connector B (28P) RR PRE- No. 10 (WHT) No. 20 (WHT) Test circuits Test point 1:Audio unit connector B (8P) Test point 2:Stereo amplifier connector B (28P) CTR PRE+ No. 1 (PNK) No. 11 (PNK) CTR PRE- No. 3 (LT GRN) No. 25 (LT GRN) SUB W PRE+ No. 5 (LT BLU) No. 10 (LT BLU) SUB W PRE- No. 7 (ORN) No. 24 (ORN) Is there continuity
YES
The PRE wires are OK. Go to step 10.
NO
There is an open in the wire (s) between the audio unit and the stereo amplifier. Replace the affected shielded harness.
- Stereo amplifier check (substitution)
-1. Substitute a known-good stereo amplifier .
-2. Reconnect all the connectors, and recheck.
Does the symptom go away?
YES
Replace the original stereo amplifier.
NO
- Determine possible failure area (speaker, others) 1
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Check the speaker (s) for any damage.
Is there any damage?
YES
Replace the faulty speaker (s) .
NO
Go to step 12.
- Determine possible failure area (speaker, others) 2
-1. Test the speaker (s) .
Is the speaker (s) OK?
YES
Go to step 13.
NO
- Open wire check (FL TWEETER lines, FR TWEETER lines)
-1. Disconnect the following connector.
Stereo amplifier connector A (18P) -2. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector A (18P): disconnected Front door tweeter 2P connector: disconnected Test circuit Test point 1:Stereo amplifier connector A (18P) Test point 2:Left front door tweeter 2P connector FL TWEETER+ No. 14 (BRN) No. 2 (BRN) FL TWEETER- No. 15 (RED) No. 1 (RED) Test circuit Test point 1:Stereo amplifier connector A (18P) Test point 2:Right front door tweeter 2P connector FR TWEETER+ No. 16 (BLU) No. 2 (BLU) FR TWEETER- No. 17 (BRN) No. 1 (BRN) Is there continuity?
YES
Replace the stereo amplifier .
NO
Repair an open in the wire (s) between the stereo amplifier and the front door tweeter.
- Determine possible failure area (speaker, others) 1
-1. Turn the vehicle to the OFF (LOCK) mode.
-2. Check the speaker (s) for any damage.
Is there any damage?
YES
Replace the faulty speaker (s) .
NO
Go to step 15.
- Determine possible failure area (speaker, others) 2
-1. Test the speaker (s) .
Is the speaker (s) OK?
YES
Go to step 16.
NO
- Open wire check (SPKR lines, SUB WOOFER lines)
-1. Reconnect all the speaker connectors .
-2. Disconnect the following connectors.
Stereo amplifier connector A (18P) Stereo amplifier connector C (8P) ANC/active sound control unit 20P connector -3. Measure the resistance between test points 1 and 2.
NOTE: If you check the RL SATE SPKR lines or the RR SATE SPKR lines, disconnect the connector at each speaker (rear speaker, rear tweeter) in the circuit one at a time, and measure the resistance.
Test condition Vehicle OFF (LOCK) mode Stereo amplifier connector A (18P): disconnected Stereo amplifier connector C (8P): disconnected ANC/active sound control unit 20P connector: disconnected Test circuits Test point 1:Stereo amplifier connector A (18P) Test point 2:Stereo amplifier connector A (18P) Resistance FL SPKR+, FL SPKR- No. 5 (GRN) No. 6 (WHT) About 2 Ω FR SPKR+, FR SPKR- No. 13 (RED) No. 12 (BLU) About 2 Ω CTR SPKR+, CTR SPKR- No. 11 (BRN) No. 18 (YEL) About 2 Ω SUB WOOFER+, SUB WOOFER- No. 2 (GRN) No. 4 (RED) About 2 Ω Test circuits Test point 1:Stereo amplifier connector C (8P) Test point 2:Stereo amplifier connector C (8P) Resistance RL SATE SPKR+, RL SATE SPKR- No. 3 (BRN) No. 4 (GRY) About 2 Ω RL SATE SPKR+, RL SATE SPKR- No. 1 (PNK) No. 2 (PUR) About 2 Ω Is the resistance OK?
YES
Replace the stereo amplifier .
NO
Repair an open in the wire (s) between the stereo amplifier and the speaker.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.