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Inspection Procedure

NOTE:
  • Turn the engine switch off before measuring the resistances of CAN bus main wires and CAN bus branch wires.
  • After the engine switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.
  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the engine switch, any other switches, or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

HINT

Operating the engine switch, any switches, or any doors triggers related ECU and sensor communication with the CAN. This communication will cause the resistance value to change.

  1. CHECK DLC3 
    1. Turn the engine switch off.
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value Result
      J21-6 (CANH) - J21-14 (CANL) Engine switch off 108 to 132 Ω A
      J21-6 (CANH) - J21-14 (CANL) Engine switch off 133 Ω or higher B
      NOTE: When the measured value is 132 Ω or more and a CAN communication system diagnostic trouble code 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.
      Fig 1: Identifying J21 Connector Terminal
      G05754157Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    B: REPAIR OR REPLACE DLC3 BRANCH LINE OR CONNECTOR (CANH, CANL) 

    A: Go to Next Step 

  2. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN BUS CHECK) 
    1. Perform "CAN Bus Check" using the Techstream (See DIAGNOSIS SYSTEM  )

      Result 

      DTC RESULT REFERENCE

      Specified Condition Proceed to
      "Engine" and "ECT" only are not displayed A
      "Gateway" only is not displayed B
      Others C

    B: Go to step  4

    C: Go to step  7

    A: Go to Next Step 

  3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR) 
    1. Turn the engine switch off
    2. Disconnect the ECM connector (A6)
    3. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      A6-14 (CANH) - A6-13 (CANL) Engine switch off 108 to 132 Ω
      4. Fig 2: Identifying ECM Connector (A6)
      G05754158Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM - CAN LH JUNCTION CONNECTOR) 

    OK: REPLACE ECM  (See REMOVAL )

  4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN LH JUNCTION CONNECTOR) 
    1. Turn the engine switch off
    2. Disconnect the gateway ECU connector (J76)
    3. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      J76-17(CA1H) - J76-18 (CA1L) Engine switch off 108 to 132 Ω
      4. Fig 3: Identifying J76 Connector Terminal
      G05754159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 5 

    OK: REPLACE GATEWAY ECU  (See NETWORK GATEWAY ECU  )

  5. RECONNECT CONNECTOR 
    1. Reconnect the gateway ECU connector (J76).
  6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN RH JUNCTION CONNECTOR GATEWAY ECU) 
    1. Disconnect the CAN main bus line connector (J84) from the CAN RH junction connector B side (w/o earth terminal).
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      J84-1 (CANH) - J84-2 (CANL) Engine switch off 108 to 132 Ω
      3. Fig 4: Identifying J84 Connector Terminal
      G05754160Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN RH JUNCTION CONNECTOR - GATEWAY ECU) 

    OK: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN LH JUNCTION CONNECTOR - CAN RH JUNCTION CONNECTOR) 

  7. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR) 
    1. Turn the engine switch off
    2. Disconnect the ECM connector (A6).
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      A6-14 (CANH) - A6-13 (CANL) Engine switch off 108 to 132 Ω
      4. Fig 5: Identifying A6 Connector Terminal
      G05754158Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 8 

    OK: REPLACE ECM  (See REMOVAL )

  8. RECONNECT CONNECTOR 
    1. Reconnect the ECM connector (A5)
  9. CHECK FOR OPEN IN CAN BUS MAIN WIRE (GATEWAY ECU - CAN LH JUNCTION CONNECTOR) 
    1. Disconnect the gateway ECU connector (J76).
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      J76-17(CA1H) - J76-18 (CA1L) Engine switch off 108 to 132 Ω
      3. Fig 6: Identifying Gateway ECU Connector (J76)
      G05754159Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 10 

    OK: REPLACE GATEWAY ECU  (See NETWORK GATEWAY ECU  )

  10. RECONNECT CONNECTOR 
    1. Reconnect the gateway ECU connector (J76)
  11. CHECK FOR OPEN IN CAN BUS MAIN WIRE (CAN RH JUNCTION CONNECTOR GATEWAY ECU) 
    1. Disconnect the CAN main bus line connector (J84) from the CAN RH junction connector B side (w/o earth terminal)
      NOTE:
      • Before disconnecting the connector, make a note of where it is connected.
      • Reconnect the connector to its original position.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      J84-1 (CANH) - J84-2 (CANL) Engine switch off 108 to 132 Ω
      3. Fig 7: Identifying J84 Connector Terminal
      G05754160Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN RH JUNCTION CONNECTOR - GATEWAY ECU) 

    OK: Go to Next Step 

  12. RECONNECT CONNECTOR 
    1. Reconnect the CAN main bus line connector (J84) to the CAN RH junction connector B side (w/o earth terminal)
  13. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ECM - CAN LH JUNCTION CONNECTOR) 
    1. Disconnect the CAN main bus line connector (J2) from the CAN LH junction connector A side (w/ earth terminal)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Value
      J2-1 (CANH) - J2-2 (CANL) Engine switch off 108 to 132 Ω
      3. Fig 8: Identifying J2 Connector Terminal
      G05754164Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM - CAN LH JUNCTION CONNECTOR) 

    OK: REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN LH JUNCTION CONNECTOR - CAN RH JUNCTION CONNECTOR) 

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