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Open in CAN Main Bus Line [05/2014 - ]: Procedure

  1. CHECK FOR OPEN IN CAN BUS LINES (DLC3 BRANCH LINE) 
    1. Disconnect the cable from the negative (-) battery terminal.
    2. Measure the resistance according to the value(s) in the chart below.
      GTY387401Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *1 DLC3

      Standard Resistance

      Tester Connection Condition Specified Condition
      D10-6 (CANH) - D10-14 (CANL) Cable disconnected from negative (-) battery terminal 114 to 126 Ω
      NOTE:

      When the measured value is 127 Ω or higher and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch line. 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 [05/2014 - ] .

    NG → REPAIR OR REPLACE CAN BRANCH LINE CONNECTED TO DLC3 

    OK: Go to next step 

  2. CHECK FOR OPEN IN CAN BUS LINES (ECM) 
    1. Disconnect the A33 ECM connector.
      GTY392866Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A33-19 (CANH) - A33-18 (CANL) Cable disconnected from negative (-) battery terminal 114 to 126 Ω

    NG → See step   3 

    OK → See step   8 

  3. CHECK FOR OPEN IN CAN BUS LINES (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)) 
    1. Reconnect the A33 ECM connector.
    2. Disconnect the A5 skid control ECU (brake actuator assembly) connector.
      GTY387112Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to Skid Control ECU (Brake Actuator Assembly))
    3. Measure the resistance according to the value(s) in the chart below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A5-26 (CANH) - A5-14 (CANL) Cable disconnected from negative (-) battery terminal 114 to 126 Ω

    NG → See step   4 

    OK → See step   7 

  4. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C) 
    1. Reconnect the A5 skid control ECU (brake actuator assembly) connector.
    2. Disconnect the wire harness connector from the D43 CAN No. 2 junction connector.
      GTY387943Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

      *a Front view of wire harness connector
      (to CAN No. 2 Junction Connector)
      *b to CAN No. 1 Junction Connector
      *c to ECM
    3. Measure the resistance according to the value(s) in the chart below.

      Standard Resistance

      Tester Connection Condition Specified Condition Connected to
      D43-1 - D43-12 Cable disconnected from negative (-) battery terminal 114 to 126 Ω CAN No. 1 junction connector
      D43-9 - D43-20 Cable disconnected from negative (-) battery terminal 114 to 126 Ω ECM

      Result

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

    B → See step   5 

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

    A → REPLACE CAN NO. 2 JUNCTION CONNECTOR 

  5. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C - CAN NO. 1 J/C) 
    1. Reconnect the wire harness connector to the D43 CAN No. 2 junction connector.
    2. Disconnect the wire harness connector from the A17 CAN No. 1 junction connector.
      GTY387950Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      TEXT IN ILLUSTRATION

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

      Standard Resistance

      Tester Connection Condition Specified Condition
      A17-7 - A17-18 Cable disconnected from negative (-) battery terminal 114 to 126 Ω

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

    OK: Go to next step 

  6. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 J/C - SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)) 
    GTY387949Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    TEXT IN ILLUSTRATION

    *a Front view of wire harness connector
    (to CAN No. 1 Junction Connector)
    *b to Skid Control ECU (Brake Actuator Assembly)
    1. Measure the resistance according to the value(s) in the chart below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A17-6 - A17-17 Cable disconnected from negative (-) battery terminal 114 to 126 Ω

    NG → REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 1 J/C - SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY)) 

    OK → REPLACE CAN NO. 1 JUNCTION CONNECTOR 

  7. REPLACE SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY). Refer to  REMOVAL [05/2014 - ] 
  8. REPLACE ECM. Refer to  REMOVAL [05/2014 - ] 
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