AUDIO AND VISUAL SYSTEM(for 8 Speakers), Diagnostic DTC:B1579

DTC Code DTC Name
B1579 Voice Recognition Microphone Disconnected

DESCRIPTION

The radio receiver assembly and map light assembly (telephone microphone assembly) are connected to each other using the microphone connection detection signal lines.

This DTC is stored when a microphone connection detection signal line is disconnected.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1579 Voice Recognition Microphone Disconnected Microphone signal is lost

  • Radio receiver assembly

  • Map light assembly

  • Telephone microphone assembly

  • Harness or connector

WIRING DIAGRAM

B002HL6E02
*a Shielded
*b Telephone Microphone Assembly
*c Map Light Assembly
*d Radio Receiver Assembly

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAP LIGHT ASSEMBLY)


    1. Disconnect the I121 radio receiver assembly connector.

    2. Disconnect the T7 map light assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I121-6 (SNS2) - T7-1 (SNS2) Always Below 1 Ω
      I121-4 (MACC) - T7-4 (MACC) Always Below 1 Ω
      I121-5 (MIN+) - T7-3 (MCO+) Always Below 1 Ω
      I121-19 (MIN-) - T7-2 (MCO-) Always Below 1 Ω
      I121-18 (SGND) - Body ground Always 10 kΩ or higher
      I121-6 (SNS2) or T7-1 (SNS2) - Body ground Always 10 kΩ or higher
      I121-4 (MACC) or T7-4 (MACC) - Body ground Always 10 kΩ or higher
      I121-5 (MIN+) or T7-3 (MCO+) - Body ground Always 10 kΩ or higher
      I121-19 (MIN-) or T7-2 (MCO-) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  2. CHECK RADIO RECEIVER ASSEMBLY


    1. B002HZNC79
      *a

      Component with harness connected

      (Radio Receiver Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      I121-18 (SGND) - Body ground Always Below 1 Ω
      I121-19 (MIN-) - Body ground Always Below 1 Ω

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      I121-4 (MACC) - Body ground Power switch on (ACC) 4 to 6 V
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE RADIO RECEIVER ASSEMBLY Click here

    OK

  3. INSPECT MAP LIGHT ASSEMBLY (TELEPHONE MICROPHONE ASSEMBLY)


    1. B002JDSE35

      Remove the map light assembly (telephone microphone assembly).

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1 (SNS2) - 2 (MCO-) Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    GO TO STEP 5 Click here

    OK

  4. CHECK MAP LIGHT ASSEMBLY


    1. B002KKNC01
      *a

      Component with harness connected

      (Map Light Assembly)

      Reconnect the radio receiver assembly connector.

    2. Reconnect the map light assembly connector.

    3. Turn the power switch on (ACC).

    4. Connect an oscilloscope to terminals T7-3 (MCO+) and T7-2 (MCO-) of the map light assembly connector.

    5. Check the waveform of the telephone microphone assembly using the oscilloscope.

      Result
      Result Proceed to
      A waveform synchronized with the voice input to the map light assembly is not output. A
      A waveform synchronized with the voice input to the map light assembly is output. B

    B

    REPLACE RADIO RECEIVER ASSEMBLY Click here

    A

  5. CHECK TELEPHONE MICROPHONE ASSEMBLY


    1. Replace the telephone microphone assembly.

      Click here

    2. Clear the DTCs.

      Click here


      Body Electrical > Navigation System > Clear DTCs

    3. Recheck for DTCs and check that no DTCs are output.

      Click here


      Body Electrical > Navigation System > Trouble Codes
      OK
      No DTCs are output.
      Result
      Proceed to
      OK
      NG

    OK

    END (TELEPHONE MICROPHONE ASSEMBLY IS DEFECTIVE)

    NG

    REPLACE MAP LIGHT ASSEMBLY Click here