DTC B1775

2018 Acura RLX BaseSECTION DTC B1775

DTC B1775  : Microphone In/Out Open or Shorted to Power

DTC Description DTC
B1775 Microphone In/Out Open or Shorted to Power  

DTC (Telematics System)

NOTE:  Check the connectors for poor connections or loose terminals.

  1. Problem verification

    -1. Clear the DTCs with the HDS.

    -2. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -3. Check for DTCs with the HDS.

    DTC Description DTC
    B1775 Microphone In/Out Open or Shorted to Power  

    Is DTC B1775 indicated?

    YES 

    The failure is duplicated, go to step 2.

    NO 

    Intermittent failure, the system is OK at this time.

  2. Shorted wire check (MIC+L line to power)

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

    -2. Disconnect the following connectors.

    Telematics control unit connector A (36P)
    Front HFL-navigation-ANC/active sound control microphone 8P connector

    -3. Turn the vehicle to the ON mode.

    -4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      Telematics control unit connector A (36P): disconnected
      Front HFL-navigation-ANC/active sound control microphone 8P connector: disconnected
    Test circuit MIC+L
    Test point 1 Front HFL-navigation-ANC/active sound control microphone 8P connector No. 2 (WHT)
    Test point 2 Body ground
    GHH352296Courtesy of HONDA, U.S.A., INC.

    Is there about 8.0 V or more?

    YES 

    There is a short to power in the wire between the telematics control unit and the front HFL-navigation-ANC/active sound control microphone. Replace the affected shielded harness.

    NO 

    The MIC+L wire is not shorted to power. Go to step 3.

  3. Determine possible failure area (MIC+L line, others)

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

    -2. Reconnect telematics control unit connector A (36P).

    -3. Turn the vehicle to the ON mode.

    -4. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      Front HFL-navigation-ANC/active sound control microphone 8P connector: disconnected
    Test circuit MIC+L
    Test point 1 Front HFL-navigation-ANC/active sound control microphone 8P connector No. 2 (WHT)
    Test point 2 Body ground
    GHH352297Courtesy of HONDA, U.S.A., INC.

    Is there about 8.0 V?

    YES 

    Go to step 5.

    NO 

    Go to step 4.

  4. Open wire check (MIC+L line)

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

    -2. Disconnect the following connector.

    Telematics control unit connector A (36P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Front HFL-navigation-ANC/active sound control microphone 8P connector: disconnected
      Telematics control unit connector A (36P): disconnected
    Test circuit MIC+L
    Test point 1 Telematics control unit connector A (36P) No. 4 (WHT)
    Test point 2 Front HFL-navigation-ANC/active sound control microphone 8P connector No. 2 (WHT)
    GHH352298Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    Replace the telematics control unit .

    NO 

    There is an open in the wire between the telematics control unit and the front HFL-navigation-ANC/active sound control microphone. Replace the affected shielded harness.

  5. Open wire check (MIC GND line)

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

    -2. Disconnect the following connector.

    Telematics control unit connector A (36P)

    -3. Check for continuity between test points 1 and 2.

    Test condition Vehicle OFF (LOCK) mode
      Front HFL-navigation-ANC/active sound control microphone 8P connector: disconnected
      Telematics control unit connector A (36P): disconnected
    Test circuit MIC GND
    Test point 1 Telematics control unit connector A (36P) No. 3 (BLU)
    Test point 2 Front HFL-navigation-ANC/active sound control microphone 8P connector No. 1 (BLU)
    GHH352299Courtesy of HONDA, U.S.A., INC.

    Is there continuity?

    YES 

    The MIC GND wire is OK. Go to step 6.

    NO 

    Repair an open in the wire between the telematics control unit and the front HFL-navigation-ANC/active sound control microphone.

  6. Shorted wire check (HFT-NAVI MIC+ line to power)

    -1. Disconnect the following connector.

    Audio-navigation unit connector F (18P)

    -2. Turn the vehicle to the ON mode.

    -3. Measure the voltage between test points 1 and 2.

    Test condition Vehicle ON mode
      Front HFL-navigation-ANC/active sound control microphone 8P connector: disconnected
      Telematics control unit connector A (36P): disconnected
      Audio-navigation unit connector F (18P): disconnected
    Test circuit HFT-NAVI MIC+
    Test point 1 Audio-navigation unit connector F (18P) No. 13 (RED)
    Test point 2 Body ground
    GHH352300Courtesy of HONDA, U.S.A., INC.

    Is there about 8.0 V or more?

    YES 

    There is a short to power in the wire between the telematics control unit and the audio-navigation unit. Replace the affected shielded harness.

    NO 

    The HFT-NAVI MIC+ wire is not shorted to power. Go to step 7.

  7. Determine possible failure area (audio-navigation unit, others)

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

    -2. Reconnect telematics control unit connector A (36P) and the front HFL-navigation-ANC/active sound control microphone 8P connector .

    -3. Clear the DTCs with the HDS.

    -4. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -5. Check for DTCs with the HDS.

    DTC Description DTC
    B1775 Microphone In/Out Open or Shorted to Power  

    Is DTC B1775 indicated?

    YES 

    Go to step 8.

    NO 

    Replace the audio-navigation unit .

  8. Front HFL-navigation-ANC/active sound control microphone check (substitution)

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

    -2. Substitute a known-good front HFL-navigation-ANC/active sound control microphone .

    -3. Clear the DTCs with the HDS.

    -4. Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

    -5. Check for DTCs with the HDS.

    DTC Description DTC
    B1775 Microphone Input/Output open or shorted to power  

    Is DTC B1775 indicated?

    YES 

    Replace the telematics control unit .

    NO 

    Replace the original front HFL-navigation-ANC/active sound control microphone.

RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

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.