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Inspection Procedure

  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL 
    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the main wire and the branch wire.
    CAUTION: Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.
    NOTE:
    • w/ Navigation System:

      After the engine switch is turned off, the HDD navigation system requires approximately 6 minutes to record various types of memory and settings. As a result, after turning the engine switch off, wait 6 minutes or more before disconnecting the cable from the negative (-) battery terminal.

    • When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See INITIALIZATION ).
  2. CHECK FOR OPEN IN CAN BUS WIRE (REAR JUNCTION BLOCK BRANCH WIRE) 
    1. Disconnect the L33 No. 2 main body ECU connector.
    2. Measure the resistance according to the value(s) in the table below.

    Standard Resistance 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    L33-11 (MPX+) - L33-12 (MPX-) Engine switch off 54 to 69 Ω

    NG: REPAIR OR REPLACE NO. 2 MAIN BODY ECU BRANCH WIRE OR CONNECTOR (MPX+, MPX-) 

    Fig 1: Checking For Open In CAN Bus Wire (Rear Junction Block Branch Wire)
    G05765017Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (NO. 2 MAIN BODY ECU - BATTERY AND BODY GROUND) 
    1. Connect the cable to the negative (-) battery terminal.
      NOTE: When disconnecting the cable, some systems need to be initialized after the cable is reconnected (See INITIALIZATION ).
    2. Disconnect the L33 No. 2 main body ECU connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      L33-7 (GND) - Body ground Always Below 1 Ω
    4. Measure the voltage according to the value(s) in the table below.
    Fig 2: Checking Harness And Connector (No. 2 Main Body ECU - Battery And Body Ground)
    G05765018Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    Standard Voltage 

    TESTER CONNECTION SPECIFIED CONDITION CHART

    Tester Connection Switch Condition Specified Condition
    L33-14 (BECU) - Body ground Always 11 to 14 V
    L33-13 (SIG) - Body ground Engine switch on (IG) 11 to 14 V

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE NO. 2 MAIN BODY ECU  (See REMOVAL )

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