HFL Does Not Respond (Without Navigation) (2018-19)

2018 Acura TLX Base, 2.4L EngSECTION HFL Does Not Respond (Without Navigation) (2018-19)
NOTE:
  1. Problem verification

    - 1. Turn the vehicle to the ON mode.

    - 2. Press the PHONE button.

    Is the Initializing screen displayed?

    YES 

    Go to step 2.

    NO 

    Intermittent failure, the system is OK at this time. If possible, have the client demonstrate the issue.

  2. System Diagnostic Mode check

    - 1. Go into the System Diagnostic Mode, and use the System Links to check the Display icon status.

    Is the Display icon green?

    YES 

    Go to step 3.

    NO 

    Go to Center display does not dim or brighten with dimmer troubleshooting .

  3. HFL diagnosis check

    - 1. Go into the System Diagnostic Mode, and select the HFL in the Unit Check menu, and check HFL, GA-NET, and USB status.

    Are HFL OK, GA-NET OK, and USB OK indicated?

    YES 

    Replace the audio unit .

    NO: HFL B1792 is indicated 

    Go to DTC B1792 troubleshooting .

    NO: HFL NG, GA-NET NG, and USB OK are indicated 

    Go to step 4.

    NO: HFL NG, GA-NET NG, and USB NG are indicated 

    Go to step 5.

  4. Open wire check (GA BUS+ line, GA BUS- line)

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

    - 2. Disconnect the following connectors.

    Hands Free Link control unit connector A (32P)
    Audio unit connector D (12P)

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

    Test condition Vehicle OFF (LOCK) mode
      Hands Free Link control unit connector A (32P): disconnected
      Audio unit connector D (12P): disconnected
    Test point 1 Audio unit connector D (12P) No. 1 - Refer to: Audio Unit Connector for Inputs and Outputs (2018), or Audio Unit Connector for Inputs and Outputs (2019)
    Test point 2 Hands Free Link control unit connector A (32P) No. 12 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)
    Test point 1 Audio unit connector D (12P) No. 7 - Refer to: Audio Unit Connector for Inputs and Outputs (2018), or Audio Unit Connector for Inputs and Outputs (2019)
    Test point 2 Hands Free Link control unit connector A (32P) No. 13 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)

    Is there continuity?

    YES 

    Replace the Hands Free Link control unit .

    NO 

    There is an open in the wire (s) between the audio unit and the Hands Free Link control unit. Replace the affected shielded harness.

  5. Determine possible failure area (GA+B line, others)

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

    - 2. Disconnect the following connector.

    Hands Free Link control unit connector A (32P)

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

    Test condition Vehicle OFF (LOCK) mode
      Hands Free Link control unit connector A (32P): disconnected
    Test point 1 Hands Free Link control unit connector A (32P) No. 32 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Go to step 7.

    NO 

    Go to step 6.

  6. Open wire check (GA+B line)

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

    Test condition Vehicle OFF (LOCK) mode
      Hands Free Link control unit connector A (32P): disconnected
    Test point 1 Audio unit connector D (12P) No. 12 - Refer to: Audio Unit Connector for Inputs and Outputs (2018), or Audio Unit Connector for Inputs and Outputs (2019)
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Repair an open in the wire between the audio unit and the Hands Free Link control unit.

    NO 

    Replace the audio unit .

  7. Determine possible failure area (GA GND line, others)

    - 1. Reconnect Hands Free Link control unit connector A (32P).

    - 2. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
    Test point 1 Hands Free Link control unit connector A (32P) No. 16 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)
    Test point 2 Body ground

    Is there less than 0.2 V?

    YES 

    Go to step 9.

    NO 

    Go to step 8.

  8. Open wire check (GA GND line)

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

    Test condition Vehicle ON mode
    Test point 1 Audio unit connector D (12P) No. 6 - Refer to: Audio Unit Connector for Inputs and Outputs (2018), or Audio Unit Connector for Inputs and Outputs (2019)
    Test point 2 Body ground

    Is there any voltage?

    YES 

    Replace the audio unit .

    NO 

    Repair an open in the wire between the audio unit and the Hands Free Link control unit.

  9. Determine possible failure area (GA SYS ON line, others)

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

    - 2. Disconnect the following connector.

    Tuner unit connector A (20P)

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

    Test condition Vehicle OFF (LOCK) mode
      Tuner unit connector A (20P): disconnected
    Test point 1 Audio unit connector D (12P) No. 8 - Refer to: Audio Unit Connector for Inputs and Outputs (2018), or Audio Unit Connector for Inputs and Outputs (2019)
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Go to step 11.

    NO 

    Go to step 10.

  10. Open wire check (GA SYS ON line)

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

    Test condition Vehicle OFF (LOCK) mode
      Tuner unit connector A (20P): disconnected
    Test point 1 Hands Free Link control unit connector A (32P) No. 24 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)
    Test point 2 Body ground

    Is there battery voltage?

    YES 

    Repair an open in the wire between the audio unit and the Hands Free Link control unit.

    NO 

    Replace the audio unit .

  11. Audio unit check

    - 1. Turn the vehicle to the ON mode.

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

    Test condition Vehicle ON mode
      Tuner unit connector A (20P): disconnected
    Test point 1 Hands Free Link control unit connector A (32P) No. 24 - Refer to: Hands Free Link Control Unit Connector for Inputs and Outputs (2018-19)
    Test point 2 Body ground

    Is there less than 0.2 V?

    YES 

    Replace the Hands Free Link control unit .

    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.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.