ACTIVE NOISE CONTROL SYSTEM, Diagnostic DTC:B1AA187

DTC Code DTC Name
B1AA187 UART Communication Between ANC and Audio Amplifier Missing Message

DESCRIPTION

This DTC is stored when an UART communication error occurs between the stereo component equalizer assembly and stereo component amplifier assembly.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1AA187 UART Communication Between ANC and Audio Amplifier Missing Message When the stereo component equalizer assembly detects a UART communication malfunction in the stereo component amplifier assembly for 4 seconds or more continuously 3 seconds after the power switch is turned on (ACC)*

  • Harness or connector

  • Stereo component amplifier assembly

  • Stereo component equalizer assembly

Tech Tips

*: Malfunction monitoring is not performed during the following conditions to prevent erroneous detection.


  • The auxiliary battery voltage is less than 9.5 V.

  • Before 3 seconds have elapsed after auxiliary battery voltage has returned to normal.

WIRING DIAGRAM

B004YDHE15
*a Stereo Component Amplifier Assembly
*b Stereo Component Equalizer Assembly

PROCEDURE


  1. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Active Noise Control > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  2. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Active Noise Control > Trouble Codes
      OK
      DTC B1AA187 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

  3. CHECK HARNESS AND CONNECTOR (STEREO COMPONENT EQUALIZER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)


    1. Disconnect the L7 stereo component equalizer assembly connector.

    2. Disconnect the L53 stereo component amplifier assembly connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      L7-2 (ACK1) - L53-2 (ACK1) Always Below 1 Ω
      L7-16 (ACK2) - L53-10 (ACK2) Always Below 1 Ω
      L7-2 (ACK1) - Body ground Always 10 kΩ or higher
      L7-16 (ACK2) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY


    1. Replace the stereo component amplifier assembly with a new or known good one.

      Click here

      Result
      Proceed to
      NEXT

    NEXT

  5. CLEAR DTC


    1. Clear the DTCs.

      Click here


      Body Electrical > Active Noise Control > Clear DTCs
      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK FOR DTC


    1. Check for DTCs.

      Click here


      Body Electrical > Active Noise Control > Trouble Codes
      OK
      DTC B1AA187 is not output.
      Result
      Proceed to
      OK
      NG

    OK

    END (STEREO COMPONENT AMPLIFIER ASSEMBLY IS DEFECTIVE)

    NG

    REPLACE STEREO COMPONENT EQUALIZER ASSEMBLY Click here