CAN COMMUNICATION SYSTEM(for LHD with Central Gateway ECU) Open in Bus 5 Main Bus Line

DESCRIPTION

There may be an open circuit in one of the bus 5 main lines when the resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU is 70 Ω or higher.

Detection Item Trouble Area
Resistance between terminals 15 (CA5H) and 16 (CA5L) of central gateway ECU is 70 Ω or higher.

  • Bus 5 CAN main wire or connector

  • Central gateway ECU

  • No. 3 CAN junction connector

  • No. 4 CAN junction connector

  • No. 1 CAN junction terminal

This malfunction is not related to the lines of a bus 5 branch or to ECUs or sensors connected a bus 5 branch.

WIRING DIAGRAM

A01X5CAE03
*a No. 3 CAN Junction Connector
*b Central Gateway ECU
*c No. 4 CAN Junction Connector
*d No. 1 CAN Junction Terminal

CAUTION / NOTICE / HINT

Note


  • Because the order of diagnosis is important to allow correct diagnosis, make sure to begin troubleshooting using How to Proceed with Troubleshooting when CAN communication system related DTCs are output Click here.

  • Before measuring the resistance of the CAN bus, turn the ignition switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors. After that, disconnect the cable from the negative (-) battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

  • After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.

Tech Tips


  • Operating the ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. CHECK FOR OPEN IN CAN BUS WIRE (CENTRAL GATEWAY ECU - NO. 3 CAN JUNCTION CONNECTOR)


    1. Disconnect the cable from the negative (-) battery terminal.

    2. A01X1MBE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Central Gateway ECU)

      Disconnect the central gateway ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      E145-15 (CA5H) - E145-16 (CA5L) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

    OK

    REPLACE CENTRAL GATEWAY ECU Click here

    NG

  2. CONNECT CONNECTOR


    1. Reconnect the E145 central gateway ECU connector.


    NEXT

  3. CHECK FOR OPEN IN CAN BUS WIRE (NO. 1 CAN JUNCTION TERMINAL - NO. 4 CAN JUNCTION CONNECTOR)


    1. A01WZ7ZE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 1 CAN Junction Terminal)

      Disconnect the No. 1 CAN junction terminal connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      K50-3 (CANH) - K50-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω

    OK

    REPLACE NO. 1 CAN JUNCTION TERMINAL

    NG

  4. CONNECT CONNECTOR


    1. Reconnect the K50 No. 1 CAN junction terminal connector.


    NEXT

  5. CHECK FOR OPEN IN CAN BUS WIRE (NO. 3 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 3 CAN junction connector.

      A01X0A8E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)

      		 *b to No. 4 CAN Junction Connector
      *c to Central Gateway ECU - -

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connect to
      E151-3 (CANH) - E151-13 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 4 CAN junction connector
      E151-5 (CANH) - E151-15 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Central gateway ECU
      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU CAN main wire) B
      NG (No. 4 CAN junction connector CAN main wire) C

    A

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 3 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU)

    C

  6. CONNECT CONNECTOR


    1. Reconnect the E151 No. 3 CAN junction connector.


    NEXT

  7. CHECK FOR OPEN IN CAN BUS WIRE (NO. 4 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 4 CAN junction connectors.

      A01X8KKE02
      Text in Illustration
      *1 No. 4 CAN Junction Connector - -
      *a

      Rear view of wire harness connector

      (to No. 4 CAN Junction Connector)

      		 - -
      Code Color (CANH Side) Color (CANL Side) Connect to
      K56 W B No. 3 CAN Junction Connector
      K57 SB B No. 1 CAN Junction Terminal

    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      K56-1 (CANH) - K56-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      K57-1 (CANH) - K57-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Result Proceed to
      OK A
      NG (No. 3 CAN junction connector CAN main wire) B
      NG (No. 1 CAN junction terminal CAN main wire) C

    A

    REPLACE NO. 4 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION CONNECTOR)

    C

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 4 CAN JUNCTION CONNECTOR - NO. 1 CAN JUNCTION TERMINAL)