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) (With Navigation) (2014 2015 2016)
- Check the vehicle battery condition first - Refer to: Battery Test (2014 2015), or Battery Test (2016 2017 2018 2019 2020) .
- 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, CD, and DVD).
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
Refer to AM/FM radio display is blank or no station information is displayed .
YES: Sound is weak or distorted in XM mode
Intermittent failure, the system is OK at this time. If the AM or FM sound is not heard, see appropriate "Poor or No Sound" troubleshooting procedure under Audio System Symptom Troubleshooting .
YES: Sound is weak or distorted in AUX mode
Refer to Auxiliary input sound is low or cannot be heard (Without Navigation) or Auxiliary input sound is low or cannot be heard (With Navigation)
YES: Sound is weak or distorted in USB mode
Refer to USB input sound is low or cannot be heard (2014 2015 2016 2017) .
YES: Sound is weak or distorted in Bluetooth audio mode
Refer to the appropriate No Sound When Bluetooth Audio Is Used procedure in SYMPTOM TROUBLESHOOTING .
YES: Sound is weak or distorted in CD mode
Refer to Audio disc does not play .
NO: No sound is heard in DVD mode
Refer to RES Disc Does Not Play Troubleshooting procedure in the appropriate Rear Entertainment System service information. .
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, RL, RR) 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-navigation unit to prevent damaging the CD/DVD player's load mechanism.
Stereo amplifier connector B (28P) Audio-navigation 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-navigation unit connector A (24P): disconnected Connector Test circuits Terminal Audio-navigation unit connector A (24P) FL PRE IN+ No. 15 (BLU) FL PRE IN- No. 16 (YEL) FR PRE IN+ No. 19 (LT BLU) FR PRE IN- No. 20 (GRY) Is there continuity?
YES
There is a short to body ground in the wires between the audio-navigation 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-navigation unit connector A (24P): disconnected Test circuits Connector: Audio-navigation unit connector A (24P) Test point 1 Test points 2 FL PRE IN+ to FL PRE IN- No. 15 (BLU) No. 16 (YEL) Test circuits Connector: Audio-navigation unit connector A (24P) Test point 1 Test points 2 FR PRE IN+ to FR PRE IN- No. 19 (LT BLU) No. 20 (GRY) Is there continuity?
YES
There is a short in the wires between the audio-navigation 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-navigation unit connector A (24P): disconnected Test circuits Test point 1:Audio-navigation unit connector A (24P) Test point 2:Stereo amplifier connector B (28P) FL PRE IN+ No. 15 (BLU) No. 9 (BLU) FL PRE IN- No. 16 (YEL) No. 23 (YEL) FR PRE IN+ No. 19 (LT BLU) No. 8 (LT BLU) FR PRE IN- No. 20 (GRY) No. 22 (GRY) 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-navigation 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-navigation unit to prevent damaging the CD/DVD player's load mechanism.
Stereo amplifier connector B (28P) Audio-navigation unit connector A (24P) Audio-navigation 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-navigation unit connector A (24P): disconnected Audio-navigation unit connector B (8P): disconnected Connector Test circuits Terminal Audio-navigation unit connector A (24P) RL PRE IN+ No. 5 (LT GRN) RL PRE IN- No. 6 (BLU) RR PRE IN+ No. 9 (PNK) RR PRE IN- No. 10 (PUR) Connector Test circuits Terminal Audio-navigation unit connector B (8P) CTR PRE IN+ No. 1 (RED) CTR PRE IN- No. 3 (BLK) SW PRE IN+ No. 5 (GRN) SW PRE IN- No. 7 (PNK) Is there continuity?
YES
There is a short to body ground in the wire (s) between the audio-navigation 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-navigation unit connector A (24P): disconnected Audio-navigation unit connector B (8P): disconnected Test circuits Connector: Audio-navigation unit connector A (24P) Test point 1 Test points 2 RL PRE IN+ to RL PRE IN- No. 5 (LT GRN) No. 6 (BLU) RR PRE IN+ to RR PRE IN- No. 9 (PNK) No. 10 (PUR) Test circuits Connector: Audio-navigation unit connector B (8P) Test point 1 Test points 2 CTR PRE IN+ to CTR PRE IN- No. 1 (RED) No. 3 (BLK) SW PRE IN+ to SW PRE IN- No. 5 (GRN) No. 7 (PNK) Is there continuity?
YES
There is a short in the wires between the audio-navigation 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-navigation unit connector A (24P): disconnected Audio-navigation unit connector B (8P): disconnected Test circuits Test point 1:Audio-navigation unit connector A (24P) Test point 2:Stereo amplifier connector B (28P) RL PRE IN+ No. 5 (LT GRN) No. 7 (LT GRN) RL PRE IN- No. 6 (BLU) No. 21 (BLU) RR PRE IN+ No. 9 (PNK) No. 6 (PNK) RR PRE IN- No. 10 (PUR) No. 20 (PUR) Test circuits Test point 1:Audio-navigation unit connector B (8P) Test point 2:Stereo amplifier connector B (28P) CTR PRE IN+ No. 1 (RED) No. 11 (RED) CTR PRE IN- No. 3 (BLK) No. 25 (BLK) SW PRE IN+ No. 5 (GRN) No. 10 (GRN) SW PRE IN- No. 7 (PNK) No. 24 (PNK) 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-navigation 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
Replace the audio-navigation unit - Refer to: Audio-Navigation Unit Connector for Inputs and Outputs (2018 2019 2020), or Audio-Navigation Unit Connector for Inputs and Outputs (2014 2015), or Audio-Navigation Unit Connector for Inputs and Outputs (2016), or Audio-Navigation Unit Connector for Inputs and Outputs (2017) .
- 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 (FR L TWR lines, FR R TWR 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 tweeter 2P connector FR L TWR+ No. 14 (WHT) No. 2 (RED) FR L TWR- No. 15 (ORN) No. 1 (BLK) Test circuit Test point 1:Stereo amplifier connector A (18P) Test point 2:Right tweeter 2P connector FR R TWR+ No. 16 (GRY) No. 2 (GRY) FR R TWR- 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 (SPK lines, FR TWR lines, SUBW lines)
-1. Reconnect all the speaker connectors.
- 2. Disconnect the following connectors.
Stereo amplifier connector A (18P) Stereo amplifier connector C (8P) - 3. Measure the resistance between test points 1 and 2.
NOTE:If you check the L D-PLR SPK lines or the R D-PLR SPK lines, disconnect the connector at each speaker (RR DR SPK) 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 Test circuits Test point 1:Stereo amplifier connector A (18P) Test point 2:Stereo amplifier connector A (18P) Resistance FR L DR SPK+, FR L DR SPK- No. 5 (GRN) No. 6 (RED) About 2 Ω FR R DR SPK+, FR R DR SPK- No. 13 (GRY) No. 12 (LT BLU) About 2 Ω CTR SPK+, CTR SPK- No. 11 (BLK) No. 18 (WHT) About 2 Ω RR L DR SPK+, RR L DR SPK- No. 10 (LT GRN) No. 9 (PUR) About 2 Ω RR R DR SPK+, RR R DR SPK- No. 8 (PNK) No. 7 (BLU) About 2 Ω SUBW L SP+, SUBW L SP- No. 2 (RED) No. 4 (WHT) About 2 Ω Test circuits Test point 1:Stereo amplifier connector C (8P) Test point 2:Stereo amplifier connector C (8P) Resistance SUBW R SP+, SUBW R SP- No. 7 (BRN) No. 8 (GRY) About 2 Ω L D-PLR SPK+, L D-PLR SPK- No. 3 (RED) No. 4 (GRN) About 2 Ω R D-PLR SPK+, R D-PLR SPK- No. 1 (BRN) No. 2 (GRY) About 2 Ω ROOF SPK+, ROOF SPK-* No. 5 (GRN) No. 6 (BLK) About 2 Ω *: With roof speaker
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.