NAVIGATION SYSTEM Mute Signal Circuit between Radio Receiver and Stereo Component Amplifier

DESCRIPTION

This circuit sends a signal to the stereo component amplifier assembly to mute noise. Because of that, the noise produced by changing the sound source ceases.

If there is an open in the circuit, noise can be heard from the speakers when changing the sound source.

If there is a short in the circuit, even though the stereo component amplifier assembly is functioning normally, no sound or only an extremely faint sound can be heard.

WIRING DIAGRAM

A001WIXE10
*a MUTE
*b Stereo Component Amplifier Assembly
*c Radio and Display Receiver Assembly

PROCEDURE


  1. INSPECT STEREO COMPONENT AMPLIFIER ASSEMBLY


    1. A001VC7C57
      *a

      Component with harness connected

      (Stereo Component Amplifier Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F76-1 (MUTE) - Body ground

      Ignition switch ACC, audio system playing

      → Changing modes

      3.5 V or higher

      → Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

  2. CHECK HARNESS AND CONNECTOR (RADIO AND DISPLAY RECEIVER ASSEMBLY - STEREO COMPONENT AMPLIFIER ASSEMBLY)


    1. Disconnect the F125 radio and display receiver assembly connector.

    2. Disconnect the F76 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
      F125-16 (MUT1) - F76-1 (MUTE) Always Below 1 Ω
      F125-16 (MUT1) or F76-1 (MUTE) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT STEREO COMPONENT AMPLIFIER ASSEMBLY (OUTPUT SIGNAL)


    1. Reconnect the F76 stereo component amplifier assembly connector.

    2. A001VZZC30
      *a

      Front view of wire harness connector

      (to Radio and Display Receiver Assembly)

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F125-16 (MUT1) - Body ground Ignition switch ACC, audio system is playing 3.5 V or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE RADIO AND DISPLAY RECEIVER ASSEMBLY Click here

    NG

    REPLACE STEREO COMPONENT AMPLIFIER ASSEMBLY Click here