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Inspection Procedure

  1. INSPECT FUSE (DOME, MPX-B) 
    1. Remove the DOME and MPX-B fuses from the engine room J/B No. 1.
    2. Measure the resistance of the fuse.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step. 

  2. CHECK WIRE HARNESS (COMBINATION METER ECU - BATTERY AND BODY GROUND) 
    1. Disconnect the J34 ECU connector.
    2. Measure the voltage and resistance of the wire harness side connector.

      Standard voltage 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Condition Specified Condition
      B (J34-23) - Body ground Always 10 to 14 V
      B (J34-24) - Body ground Always 10 to 14 V

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      E2 (J34-1) - Body ground Below 1 ohms
      ES (J34-13) - Body ground Below 1 ohms

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step. 

    Fig 1: Identifying Combination Meter Connector Terminals
    G04051874Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. CHECK RESISTANCE OF COMMUNICATION LINE 
    1. Disconnect the J34, J49, J76, A27 and J58 ECU connectors.
    2. Measure the resistance between the specified terminals on the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION AND SPECIFIED CONDITION TABLE

      Tester Connection Specified Condition
      MPX- (J34-18) - MPX1 (J49-3)(3) Below 1 ohms
      MPX- (J34-18) - MPI1 (J76-4)(4) Below 1 ohms
      MPX+ (J34-6) - MPX2 (A27-6)(1) Below 1 ohms
      MPX+ (J34-6) - MDX- (J58-31)(2) Below 1 ohms
      (1) w/ Adaptive front-lighting system
      (2) w/o Adaptive front-lighting system
      (3) w/ Tire Pressure Warning System
      (4) w/o Tire Pressure Warning System
      Fig 2: Identifying Tire Pressure Monitor ECU Connector Terminals
      G04051875Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Result 

      RESULT DESCRIPTION TABLE

      Result Proceed to
      Both are OK A
      One is OK B
      Both are NG C

    B: REPLACE COMBINATION METER ECU AND REPAIR OR REPLACE HARNESS OR CONNECTOR 

    C: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE COMBINATION METER ECU 

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