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Inspection Procedure

  1. INSPECT FUSE (RAD NO. 1, RAD NO. 2, ACC) 
    1. Disconnect the RAD NO. 1 and RAD NO. 2 fuses from the engine room No. 1 junction block.
    2. Disconnect the ACC fuse from the main body ECU RH.
    3. Measure the resistance of the fuses.

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  2. CHECK WIRE HARNESS (AMPLIFIER - BATTERY AND BODY GROUND) 
    1. Disconnect the U29, U31 and U42 amplifier connectors.
    2. Measure the resistance of the wire harness side connector.

      Standard resistance: 

      for CD changer models 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      U42-2 (GND)- Body ground Below 1 Ω
      U42-6 (GND2) - Body ground Below 1 Ω

      for DVD changer models 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      U31-16 (GND) - Body ground Below 1 Ω
      U31-15 (GND2) - Body ground Below 1 Ω
    3. Measure the voltage of the wire harness side connectors.

      Standard voltage: 

      for CD changer models 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      U42-1 (+B) - Body ground Always 10 to 14 V
      U42-3 (+B2) - Body ground Always 10 to 14 V
      U29-12 (ACC) - Body ground Engine switch on (ACC) 10 to 14 V

      for DVD changer models 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      U31-1 (+B) - Body ground Always 10 to 14 V
      U31-10 (+B2) - Body ground Always 10 to 14 V
      U29-12 (ACC) - Body ground Engine switch on (ACC) 10 to 14 V
    Fig 1: Identifying Stereo Component Amplifier Connector Terminals
    G05299581Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE