AUDIO AND VISUAL SYSTEM (w/o Navigation System) Dimmer Signal Circuit

DESCRIPTION

The radio receiver assembly uses this circuit to communicate with the main body ECU (cowl side junction block LH) via a direct line. The main body ECU (cowl side junction block LH) uses this circuit to send an auto dimmer signal to the radio receiver assembly. The main body ECU (cowl side junction block LH) detects the position of the light control switch according to the resistance. When the light control switch is set to the head/tail position, the resistance between the head/tail terminal and body ground is below 1 Ω. When the light control switch is set to the head/tail position, the main body ECU (cowl side junction block LH) sends an auto dimmer signal to the radio receiver assembly. When the radio receiver assembly receives an auto dimmer signal from the main body ECU (cowl side junction block LH), the radio receiver assembly causes instrument panel illumination to be dimmed.

WIRING DIAGRAM

A015A3XE06

INSPECTION PROCEDURE

PROCEDURE


  1. INSPECT MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)


    1. A0159C3E03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Radio Receiver Assembly)

      Disconnect the F19 radio receiver assembly connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      F19-20 (ADIM) - Body ground Engine switch on (IG), automatic light control sensor covered by hand, and light control switch tail or head position 11 to 14 V

    NG

    CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAIN BODY ECU) Click here

    OK

  2. INSPECT RADIO RECEIVER ASSEMBLY


    1. Disconnect the F1 radio receiver assembly connector.

    2. A0156PBE42
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Radio Receiver Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F1-20 (GND) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE RADIO RECEIVER ASSEMBLY Click here

  3. CHECK HARNESS AND CONNECTOR (RADIO RECEIVER ASSEMBLY - MAIN BODY ECU)


    1. Disconnect the F19 radio receiver assembly and E2 main body ECU (cowl side junction block LH) connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E2-16 (ACAN) - F19-20 (ADIM) Always Below 1 Ω
      F19-20 (ADIM) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)