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Open in CAN Main Bus Line: Procedure

  1. CHECK FOR OPEN IN CAN BUS WIRE (DLC3 BRANCH WIRE) 
    1. Turn the power switch off.
    2. Measure the resistance according to the value(s) in the table below.
      Fig 1: Inspecting DLC3 Branch Wire And CAN No. 1 Bus Main Wire (CANH - CANL)
      GTY235853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      L61-6 (CANH) - L61-14 (CANL) Power switch off 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *1 DLC3
      NOTE:

      When the measured value is 133 Ω or higher and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch wire. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area. Refer to HOW TO PROCEED WITH TROUBLESHOOTING .

    NG → REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 

    OK: Go to next step 

  2. CHECK FOR OPEN IN CAN BUS WIRE (ECM) 
    1. Disconnect the ECM connector.
      Fig 2: Identifying ECM Connector Terminals
      GTY232436Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to ECM)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      A57-13 (CANH) - A57-5 (CANL) Power switch off 108 to 132 Ω

    NG → See step   3 

    OK → See step   7 

  3. CHECK FOR OPEN IN CAN BUS WIRE (COMBINATION METER) 
    1. Reconnect the ECM connector.
    2. Disconnect the combination meter connector.
      Fig 3: Identifying DLC3 Connector Terminals
      GTY216622Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to Combination Meter)
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      L27-10 (CANH) - L27-11 (CANL) Power switch off 108 to 132 Ω

    NG → See step   4 

    OK → See step   8 

  4. CHECK FOR OPEN IN CAN BUS WIRE (CAN NO. 1 J/C) 
    1. Reconnect the combination meter connector.
    2. Disconnect the CAN No. 1 junction connector.
      Fig 4: Identifying L94 Connector Terminals
      GTY216578Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to CAN No. 1 Junction Connector)
      *2 to Combination Meter
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      L94-1 (CANH) - L94-12 (CANL) Power switch off 108 to 132 Ω

    NG → REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - COMBINATION METER) 

    OK: Go to next step 

  5. CHECK FOR OPEN IN CAN BUS WIRE (CAN NO. 1 J/C - CAN NO. 2 J/C) 
    1. Measure the resistance according to the value(s) in the table below.
      Fig 5: Identifying L94 Connector Terminals
      GTY216463Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard Resistance

      Tester Connection Switch Condition Specified Condition
      L94-7 (CANH) - L94-18 (CANL) Power switch off 108 to 132 Ω
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to CAN No. 1 Junction Connector)
      *2 to CAN No. 2 Junction Connector

    NG → See step   6 

    OK → REPLACE CAN NO. 1 JUNCTION CONNECTOR 

  6. CHECK FOR OPEN IN CAN BUS WIRE (CAN NO. 2 J/C) 
    1. Reconnect the CAN No. 1 junction connector.
    2. Disconnect the CAN No. 2 junction connector.
      Fig 6: Identifying DLC3 Connector Terminals
      GTY221286Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Switch Condition Specified Condition Connected to
      L95-3 (CANH) - L95-14 (CANL) Power switch off 108 to 132 Ω CAN No. 1 junction connector
      L95-9 (CANH) - L95-20 (CANL) Power switch off 108 to 132 Ω ECM
      TEXT IN ILLUSTRATION

      *1 Front view of wire harness connector
      (to CAN No. 2 Junction Connector)
      *2 to CAN No. 1 Junction Connector
      *3 to ECM

      Result

      Result Proceed to
      OK A
      NG (to ECM main wire) B
      NG (to CAN No. 1 junction connector main wire) C

    B → REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 J/C - ECM) 

    C → REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 1 J/C - CAN NO. 2 J/C) 

    A → REPLACE CAN NO. 2 JUNCTION CONNECTOR 

  7. REPLACE ECM. Refer to  REMOVAL 
  8. REPLACE METER CIRCUIT PLATE NO. 3 (COMBINATION METER ECU). Refer to  DISASSEMBLY 
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