CAN COMMUNICATION SYSTEM Open in CAN Main Bus Line

DESCRIPTION

There may be an open circuit one of the CAN V1 bus main lines and/or a DLC3 branch line when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 70 Ω or higher.

Symptom Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of DLC3 is 70 Ω or higher.

  • DLC3 branch line or connector

  • CAN main bus line or connector

  • ECM

  • Combination meter assembly

  • CAN No. 1 junction connector

  • CAN No. 2 junction connector

  • CAN No. 3 junction connector

WIRING DIAGRAM

A003V6DE01

INSPECTION PROCEDURE

Note


  • Turn the power switch off before measuring the resistances between CAN main bus lines and between CAN branch lines.

  • Turn the power switch off before inspecting CAN bus lines for a ground short.

  • After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power 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.

Tech Tips


  • Operating the power switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • 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 LINES (DLC3 BRANCH LINE)


    1. Turn the power switch off.

    2. A003YN4E31
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H44-6 (CANH) - H44-14 (CANL) Power switch off 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 DLC3 branch line. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area Click here.


    NG

    REPAIR OR REPLACE CAN BRANCH LINE CONNECTED TO DLC3

    OK

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


    1. A003XUOE06
      Text in Illustration
      *a

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      A60-13 (CANH) - A60-5 (CANL) Power switch off 108 to 132 Ω
      Result
      Result Proceed to
      OK (for 2ZR-FXE) A
      OK (for 5ZR-FXE) B
      NG C

    B

    REPLACE ECM Click here

    C

    CHECK FOR OPEN IN CAN BUS LINES (COMBINATION METER ASSEMBLY) Click here

    A

    REPLACE ECM Click here

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


    1. Reconnect the ECM connector.

    2. A003XCVE84
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      H19-32 (CANH) - H19-31 (CANL) Power switch off 108 to 132 Ω

    NG

    CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C) Click here

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

  4. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C)


    1. Reconnect the combination meter assembly connector.

    2. A003WY8E72
      Text in Illustration
      *a

      Front view of wire harness connector

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

      Disconnect the wire harness connector from the CAN No. 2 junction connector rear side.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition Connected to
      H104-1 (CANH) - H104-2 (CANL) Power switch off 108 to 132 Ω CAN No. 1 junction connector
      H104-4 (CANH) - H104-5 (CANL) Power switch off 108 to 132 Ω CAN No. 3 junction connector
      Result
      Result Proceed to
      OK A
      NG (CAN No. 1 junction connector main line) B
      NG (CAN No. 3 junction connector main line) C

    B

    CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C - CAN NO. 1 J/C) Click here

    C

    CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 J/C) Click here

    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 CAN No. 2 junction connector rear side.

    2. A003VCVE26
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to CAN No. 2 Junction Connector
      *c for LHD
      *d for RHD

      Disconnect the instrument panel wire from the CAN No. 1 junction connector.

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

      Standard Resistance
      for LHD
      Tester Connection Switch Condition Specified Condition
      H112-6 (CANH) - H112-12 (CANL) Power switch off 108 to 132 Ω
      for RHD
      Tester Connection Switch Condition Specified Condition
      H141-6 (CANH) - H141-12 (CANL) Power switch off 108 to 132 Ω

    NG

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

    OK

  6. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 J/C - ECM)


    1. A003VCVE27
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *b to ECM
      *c for LHD
      *d for RHD

      Disconnect the engine room main wire from the CAN No. 1 junction connector.

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

      Standard Resistance
      for LHD
      Tester Connection Switch Condition Specified Condition
      A57-1 (CANH) - A57-7 (CANL) Power switch off 108 to 132 Ω
      for RHD
      Tester Connection Switch Condition Specified Condition
      A71-1 (CANH) - A71-7 (CANL) Power switch off 108 to 132 Ω

    NG

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

    OK

    REPLACE CAN NO. 1 JUNCTION CONNECTOR

  7. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 J/C)


    1. Reconnect the wire harness connector to the CAN No. 2 junction connector rear side.

    2. A003VCVE28
      Text in Illustration
      *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
      *d for LHD
      *e for RHD

      Disconnect the instrument panel wire from the CAN No. 3 junction connector.

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

      Standard Resistance
      for LHD
      Tester Connection Switch Condition Specified Condition Connected to
      H113-5 (CANH) - H113-11 (CANL) Power switch off 108 to 132 Ω CAN No. 2 junction connector
      H113-6 (CANH) - H113-12 (CANL) Power switch off 108 to 132 Ω Combination meter assembly
      for RHD
      Tester Connection Switch Condition Specified Condition Connected to
      H142-5 (CANH) - H142-11 (CANL) Power switch off 108 to 132 Ω CAN No. 2 junction connector
      H142-6 (CANH) - H142-12 (CANL) Power switch off 108 to 132 Ω Combination meter assembly
      Result
      Result Proceed to
      OK A
      NG (CAN No. 2 junction connector main line) B
      NG (Combination meter assembly main line) C

    B

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 2 J/C - CAN NO. 3 J/C)

    C

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (CAN NO. 3 J/C - COMBINATION METER ASSEMBLY)

    A

    REPLACE CAN NO. 3 JUNCTION CONNECTOR