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IG Power Source Circuit: Procedure

  1. INSPECT FUSE (ECU-IG RH) 
    1. Remove the ECU-IG RH fuse from the main body ECU RH (cowl side junction block RH).
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      ECU-IG RH fuse Always Below 1 Ω

    NG → REPLACE FUSE 

    OK: Go to next step 

  2. INSPECT MULTIPLEX TILT AND TELESCOPIC ECU (IG TERMINAL VOLTAGE) 
    1. Disconnect the J28 connector from the multiplex tilt and telescopic ECU.
      Fig 1: Identifying J28 Connector Terminals Identification
      GTY283891Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      J28-8 (IG) - J28-11 (GND) Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Multiplex Tilt and Telescopic ECU)

    NG → See step   3 

    OK → See step   5 

  3. CHECK HARNESS AND CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - BODY GROUND) 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 2: Identifying J28 Connector Terminals Identification
      GTY285939Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Condition Specified Condition
      J28-11 (GND) - Body ground Always Below 1 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Multiplex Tilt and Telescopic ECU)

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH) - BATTERY) 
    1. Measure the voltage according to the value(s) in the table below.
      Fig 3: Identifying RA Connector Terminals
      GTY264091Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Voltage

      Tester Condition Switch Condition Specified Condition
      RA-1 - Body ground Engine switch on (IG) 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Component with harness connected
      (Main Body ECU RH (Cowl Side Junction Block RH))

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR (MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH) - BATTERY) 

    OK → REPAIR OR REPLACE HARNESS OR CONNECTOR (MULTIPLEX TILT AND TELESCOPIC ECU - MAIN BODY ECU RH) 

  5. PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to  PROBLEM SYMPTOMS TABLE