Auxiliary input sound is low or cannot be heard (Without Navigation)

2018 Acura RLX BaseSECTION Auxiliary input sound is low or cannot be heard (Without Navigation)

NOTE: 

  • Check the vehicle battery condition first .
  • Use auxiliary stereo cables with 3.5 mm ends only.
  • Auxiliary accessories may be played on the audio unit using the auxiliary input.
  • Check the connectors for poor connections or loose terminals.
  1. Problem verification

    -1. Turn the vehicle to the ON mode.

    -2. Turn on the audio system, and connect an auxiliary accessory to the auxiliary input jack.

    -3. Check the auxiliary audio source sound.

    Is the sound normal?

    YES 

    Intermittent failure, the system is OK at this time.

    NO 

    The failure is duplicated, go to step 2.

  2. Determine possible failure area (volume level, others)

    -1. Make sure the auxiliary accessory volume is set to high.

    Is the volume set to high?

    YES 

    Go to step 3.

    NO 

    Raise the auxiliary accessory volume to high. Make sure the audio unit volume is turned down before rechecking.

  3. Determine possible failure area (auxiliary audio accessory, others)

    -1. Substitute a known-good auxiliary audio accessory and/or auxiliary stereo cable, and recheck.

    Does the auxiliary audio accessory operate properly?

    YES 

    Original auxiliary audio accessory or auxiliary stereo cable is faulty.

    NO 

    Go to step 4.

  4. Shorted wire check (AUX lines)

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

    -2. Disconnect the following connectors.

    Audio unit connector C (20P)
    Auxiliary jack assembly 5P connector

    -3. Check for continuity between these test points and body ground individually.

    Test condition Vehicle OFF (LOCK) mode
      Audio unit connector C (20P): disconnected
      Auxiliary jack assembly 5P connector: disconnected
    Connector  Test circuit  Terminal 
    Audio unit connector C (20P) AUX SGND No. 8 (BRN)
    AUX R CH No. 17 (ORN)
    AUX L CH No. 18 (YEL)
    GHH340871Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    There is a short to body ground in the wire (s) between the audio unit and the auxiliary jack assembly. Repair or replace the affected harness.

    NO 

    The AUX wires are not shorted to ground. Go to step 5.

  5. Shorted wire check (SH AUX line to another lines)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Audio unit connector C (20P): disconnected
      Auxiliary jack assembly 5P connector: disconnected
    Test circuit SH AUX, AUX L CH
    Test point 1 Audio unit connector C (20P) No. 7 (GRY)
    Test point 2 Audio unit connector C (20P) No. 18 (YEL)
    Test circuit SH AUX, AUX R CH
    Test point 1 Audio unit connector C (20P) No. 7 (GRY)
    Test point 2 Audio unit connector C (20P) No. 17 (ORN)
    GHH340872Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    There is a short in the wires between the audio unit and the auxiliary jack assembly. Replace the affected shielded harness.

    NO 

    The SH AUX wire is OK. Go to step 6.

  6. Shorted wire check (AUX SGND line to another lines)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Audio unit connector C (20P): disconnected
      Auxiliary jack assembly 5P connector: disconnected
    Test circuit AUX SGND, AUX L CH
    Test point 1 Audio unit connector C (20P) No. 8 (BRN)
    Test point 2 Audio unit connector C (20P) No. 18 (YEL)
    Test circuit AUX SGND, AUX R CH
    Test point 1 Audio unit connector C (20P) No. 8 (BRN)
    Test point 2 Audio unit connector C (20P) No. 17 (ORN)
    GHH340873Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    There is a short in the wires between the audio unit and the auxiliary jack assembly. Replace the affected shielded harness.

    NO 

    The AUX SGND wire is not shorted. Go to step 7.

  7. Open wire check (AUX lines)

    -1. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Audio unit connector C (20P): disconnected
      Auxiliary jack assembly 5P connector: disconnected
    Test circuit  Test point 1:Audio unit connector C (20P)  Test point 2:Auxiliary jack assembly 5P connector 
    AUX GND No. 6 (YEL) No. 4 (YEL)
    AUX SGND No. 8 (BRN) No. 3 (PNK)
    AUX DET No. 16 (PUR) No. 5 (PUR)
    AUX R CH No. 17 (ORN) No. 1 (GRN)
    AUX L CH No. 18 (YEL) No. 2 (BLU)
    GHH340874Courtesy of HONDA, U.S.A., INC.
    GHH340875Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The AUX wires are OK. Go to step 8.

    NO 

    There is an open in the wire (s) between the audio unit and the auxiliary jack assembly. Repair or replace the affected harness.

  8. Auxiliary jack assembly check (substitution)

    -1. Substitute a known-good auxiliary jack assembly .

    -2. Reconnect all the connectors, and recheck.

    Does the symptom go away?

    YES 

    Replace the original auxiliary jack assembly.

    NO 

    Replace the audio unit .

RENDER: 1.0x

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.
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