CAN COMMUNICATION SYSTEM(w/ Central Gateway ECU) 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 line or connector

  • ECM

  • Combination meter assembly

  • No. 1 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

B0042Y9E06

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 or any 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 negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices before proceeding with work.

    Click here

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

    DTC check procedure: Turn the ignition switch to ON and wait at least 31 seconds, and then drive the vehicle at a speed of 20 km/h (12 mph) or more for 303 seconds or more.

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

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


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

    2. Disconnect the E139 central gateway ECU (network gateway ECU) connector.

    3. B00446TC03
      *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
      E139-18 (CA4H) - E139-17 (CA4L) Cable disconnected from negative (-) 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

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


    1. Disconnect the E46 combination meter assembly connector.

    2. B0042U0C70
      *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
      E46-32 (CANH) - E46-31 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Result Proceed to
      OK A
      NG (for 1NR-FE or 1ZR-FAE) B
      NG (for 1ND-TV with Glow Plug Controller) C

    A

    REPLACE COMBINATION METER ASSEMBLY Click here

    C

    CHECK FOR OPEN IN CAN MAIN BUS LINES (ECM) Click here

    B

  3. CHECK FOR OPEN IN CAN MAIN BUS LINES (ECM)


    1. Reconnect the E46 combination meter assembly connector.

    2. Disconnect the A50 ECM connector.

    3. B0042BPC54
      *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
      A50-13 (CANH) - A50-26 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Result Proceed to
      OK (for 1NR-FE) A
      OK (for 1ZR-FAE) B
      NG C

    A

    REPLACE ECM Click here

    B

    REPLACE ECM Click here

    C

    GO TO STEP 5 Click here

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


    1. Reconnect the E46 combination meter assembly connector.

    2. Disconnect the A169 ECM connector.

    3. B0042BPC58
      *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
      A169-26 (CANH) - A169-25 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Result
      OK
      NG

    OK

    REPLACE ECM Click here

    NG

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


    1. Reconnect the A50 or A169 ECM connector.

    2. Disconnect the E57 No. 3 CAN junction connector.

    3. B004333C68
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)
      *b to Combination Meter Assembly
      *c to No. 1 CAN Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      E57-4 (CANH) - E57-15 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Combination meter assembly
      E57-5 (CANH) - E57-16 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction connector
      Result
      Result Proceed to
      OK A
      NG (Line to Combination meter assembly) B
      NG (Line to No. 1 CAN junction connector) C

    A

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    B

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

    C

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


    1. Reconnect the E57 No. 3 CAN junction connector.

    2. Disconnect the A32 No. 1 CAN junction connector.

    3. B004333C69
      *a

      Front view of wire harness connector

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A32-1 (CANH) - A32-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 3 CAN junction connector
      A32-6 (CANH) - A32-17 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω ECM
      Result
      Result Proceed to
      OK A
      NG (Line to No. 3 CAN junction connector) B
      NG (Line to ECM) C

    A

    REPLACE NO. 1 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN BUS LINES OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION CONNECTOR)

    C

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