CAN COMMUNICATION SYSTEM Open in Bus 2 Main Bus Line

DESCRIPTION

There may be an open circuit in one of the CAN main bus lines and/or a central gateway ECU (network gateway ECU) branch line when the resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.

Symptom Trouble Area
Resistance between terminals 18 (CA4H) and 17 (CA4L) of the central gateway ECU (network gateway ECU) is 70 Ω or higher.

  • CAN main bus lines or connector

  • Central gateway ECU (network gateway ECU) branch lines or connector

  • ECM

  • Combination meter assembly

  • No. 1 CAN junction connector

  • No. 2 CAN junction connector

  • No. 3 CAN junction connector

This malfunction is not related to the lines of a CAN branch except the central gateway ECU (network gateway ECU) branch lines or to ECUs or sensors connected to a CAN branch.

WIRING DIAGRAM

Figure 1. for LHD

B001N0QE02

Figure 2. for RHD

B001N0QE03

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 power switch off and leave the vehicle for 1 minute or more without operating the key or any switches, or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work.

    Click here

  • After the repair, perform the CAN bus check and check that all the ECUs and sensors connected to the CAN communication system are displayed as normal.

    Click here

Tech Tips


  • Before disconnecting related connectors for inspection, push in on each connector body to check that the connector is not loose or disconnected.

  • When a connector is disconnected, check that the terminals and connector body are not cracked, deformed or corroded.

PROCEDURE


  1. CHECK VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      for LHD A
      for RHD B

    B

    CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) BRANCH LINE) Click here

    A

  2. CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) BRANCH LINE)


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

    2. Disconnect the H188 central gateway ECU (network gateway ECU) connector.

    3. B001MPJC77
      *a

      Front view of wire harness connector

      (to Central Gateway ECU (Network Gateway ECU))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H188-18 (CA4H) - H188-17 (CA4L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

      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 central gateway ECU (network gateway ECU) branch line. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area.

      Click here

      Result
      Result
      OK
      NG

    NG

    REPAIR OR REPLACE CAN BRANCH LINES CONNECTED TO CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

    OK

  3. CHECK FOR OPEN IN CAN BUS LINES (COMBINATION METER ASSEMBLY)


    1. Reconnect the H188 central gateway ECU (network gateway ECU) connector.

    2. Disconnect the H19 combination meter assembly connector.

    3. B001LSBC23
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H19-32 (CANH) - H19-31 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

  4. CHECK FOR OPEN IN CAN BUS LINES (ECM)


    1. Reconnect the H19 combination meter assembly connector.

    2. Disconnect the A60 ECM connector.

    3. B001KGSC48
      *a

      Front view of wire harness connector

      (to ECM)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A60-13 (CANH) - A60-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result Proceed to
      OK (for 2ZR-FXE) A
      OK (for 5ZR-FXE) B
      NG C

    A

    REPLACE ECM Click here

    B

    REPLACE ECM Click here

    C

  5. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 JUNCTION CONNECTOR)


    1. Reconnect the A60 ECM connector.

    2. Disconnect the H104 CAN No. 2 junction connector.

    3. B001NBKC72
      *a

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)
      *b to CAN No. 1 Junction Connector
      *c to CAN No. 3 Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H104-1 (CANH) - H104-2 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 1 junction connector
      H104-4 (CANH) - H104-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 3 junction connector
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 1 junction connector) B
      NG (Line to CAN No. 3 junction connector) C

    A

    REPLACE CAN NO. 2 JUNCTION CONNECTOR

    C

    CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 JUNCTION CONNECTOR) Click here

    B

  6. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 JUNCTION CONNECTOR - CAN NO. 2 JUNCTION CONNECTOR)


    1. Reconnect the H104 CAN No. 2 junction connector.

    2. Disconnect the H112 CAN No. 1 junction connector.

    3. B001KZHC85
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to CAN No. 2 Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H112-6 (CANH) - H112-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 2 junction connector
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 2 junction connector) B

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 1 JUNCTION CONNECTOR - CAN NO. 2 JUNCTION CONNECTOR)

    A

  7. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 JUNCTION CONNECTOR - ECM)


    1. Disconnect the A57 CAN No. 1 junction connector.

    2. B001KZHC86
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to ECM

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A57-1 (CANH) - A57-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      Result
      Result Proceed to
      OK A
      NG (Line to ECM) B

    A

    REPLACE CAN NO. 1 JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 1 JUNCTION CONNECTOR - ECM)

  8. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 JUNCTION CONNECTOR)


    1. Reconnect the H104 CAN No. 2 junction connector.

    2. Disconnect the H113 CAN No. 3 junction connector.

    3. B001KZHC87
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)
      *b to CAN No. 2 Junction Connector
      *c to Combination Meter Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H113-5 (CANH) - H113-11 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 2 junction connector
      H113-6 (CANH) - H113-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Combination meter assembly
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 2 junction connector) B
      NG (Line to Combination meter assembly) C

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 2 JUNCTION CONNECTOR - CAN NO. 3 JUNCTION CONNECTOR)

    C

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 3 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)

  9. CHECK FOR OPEN IN CAN BUS LINES (CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) BRANCH LINE)


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

    2. Disconnect the H188 central gateway ECU (network gateway ECU) connector.

    3. B001MPJC77
      *a

      Front view of wire harness connector

      (to Central Gateway ECU (Network Gateway ECU))

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H188-18 (CA4H) - H188-17 (CA4L) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

      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 central gateway ECU (network gateway ECU) branch line. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area.

      Click here

      Result
      Result
      OK
      NG

    NG

    REPAIR OR REPLACE CAN BRANCH LINES CONNECTED TO CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU)

    OK

  10. CHECK FOR OPEN IN CAN BUS LINES (COMBINATION METER ASSEMBLY)


    1. Reconnect the H188 central gateway ECU (network gateway ECU) connector.

    2. Disconnect the H19 combination meter assembly connector.

    3. B001LSBC23
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H19-32 (CANH) - H19-31 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

  11. CHECK FOR OPEN IN CAN BUS LINES (ECM)


    1. Reconnect the H19 combination meter assembly connector.

    2. Disconnect the A60 ECM connector.

    3. B001KGSC48
      *a

      Front view of wire harness connector

      (to ECM)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A60-13 (CANH) - A60-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

  12. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 JUNCTION CONNECTOR)


    1. Reconnect the A60 ECM connector.

    2. Disconnect the H104 CAN No. 2 junction connector.

    3. B001NBKC72
      *a

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)
      *b to CAN No. 1 Junction Connector
      *c to CAN No. 3 Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H104-1 (CANH) - H104-2 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 1 junction connector
      H104-4 (CANH) - H104-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 3 junction connector
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 1 junction connector) B
      NG (Line to CAN No. 3 junction connector) C

    A

    REPLACE CAN NO. 2 JUNCTION CONNECTOR

    C

    CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 JUNCTION CONNECTOR) Click here

    B

  13. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 JUNCTION CONNECTOR - CAN NO. 2 JUNCTION CONNECTOR)


    1. Reconnect the H104 CAN No. 2 junction connector.

    2. Disconnect the H141 CAN No. 1 junction connector.

    3. B001KZHC88
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to CAN No. 2 Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H141-6 (CANH) - H141-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 2 junction connector
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 2 junction connector) B

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 1 JUNCTION CONNECTOR - CAN NO. 2 JUNCTION CONNECTOR)

    A

  14. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 JUNCTION CONNECTOR - ECM)


    1. Disconnect the A71 CAN No. 1 junction connector.

    2. B001KZHC89
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to ECM

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A71-1 (CANH) - A71-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω ECM
      Result
      Result Proceed to
      OK A
      NG (Line to ECM) B

    A

    REPLACE CAN NO. 1 JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 1 JUNCTION CONNECTOR - ECM)

  15. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 JUNCTION CONNECTOR)


    1. Reconnect the H104 CAN No. 2 junction connector.

    2. Disconnect the H142 CAN No. 3 junction connector.

    3. B001KZHC90
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)
      *b to CAN No. 2 Junction Connector
      *c to Combination Meter Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H142-5 (CANH) - H142-11 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 2 junction connector
      H142-6 (CANH) - H142-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Combination meter assembly
      Result
      Result Proceed to
      OK A
      NG (Line to CAN No. 2 junction connector) B
      NG (Line to Combination meter assembly) C

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 2 JUNCTION CONNECTOR - CAN NO. 3 JUNCTION CONNECTOR)

    C

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (CAN NO. 3 JUNCTION CONNECTOR - COMBINATION METER ASSEMBLY)