CAN COMMUNICATION SYSTEM Check CAN Bus Lines for Short Circuit

DESCRIPTION

There may be a short circuit in the CAN bus main wire and/or CAN branch wire when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is below 54 Ω.

Symptom Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of DLC3 is below 54 Ω.
  • Short in CAN bus main wire

  • Short in CAN bus branch wire

  • Combination meter assembly

  • ECM

  • Power steering ECU assembly

  • Center airbag sensor assembly

  • Air conditioning amplifier assembly*3

  • Skid control ECU (brake actuator assembly)

  • Steering angle sensor (spiral cable with sensor sub-assembly)

  • Yaw rate and acceleration sensor

  • Main body ECU (driver side junction block assembly)

  • AWD control ECU*1

  • Certification ECU (smart key ECU assembly)*2

  • Power management control ECU*2

  • Navigation receiver assembly*4

  • Radio and display receiver assembly*5

  • CAN No. 1 junction connector

  • CAN No. 2 junction connector

*1: for AWD

*2: w/ Smart entry and start system

*3: w/o Smart entry and start system

*4: for Navigation receiver type

*5: for Radio and display type

WIRING DIAGRAM

A01EK6BE03
A01ELCUE09

INSPECTION PROCEDURE

Note


  • Turn the ignition switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.

  • Turn the ignition switch off before inspecting CAN bus wires for a ground short.

  • After the ignition 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 ignition 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 ignition 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 SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - CAN NO. 2 J/C)


    1. Turn the ignition switch off.

    2. A01EKZ3E32
      Text in Illustration
      *1

      Front view of wire harness connector

      (to CAN No.1 Junction Connector)

      *2 to CAN No. 2 Junction Connector

      Disconnect the CAN No. 1 junction connector (D56).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D56-9 (CANH) - D56-20 (CANL) Ignition switch off 108 to 132 Ω

    NG
    OK
  2. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - ECM)


    1. A01EKZ3E33
      Text in Illustration
      *1

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *2 to ECM

      Disconnect the CAN No. 1 junction connector (A44).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A44-4 (CANH) - A44-15 (CANL) Ignition switch off 108 to 132 Ω

    NG
    OK
  3. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY))


    1. A01EIZEE61
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU (Brake Actuator Assembly))

      Disconnect the skid control ECU (brake actuator assembly) connector.

    2. A01EKZ3E35
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *3 to Skid Control ECU (Brake Actuator Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A44-1 (CANH) - A44-12 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  4. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - AIR CONDITIONING AMPLIFIER ASSEMBLY)

    Tech Tips

    For vehicles with smart entry and start system, go to the next step.


    1. A01EJ59E17
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Air Conditioning Amplifier Assembly)

      Disconnect the air conditioning amplifier assembly connector.

    2. A01EL64E18
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *3 to Air Conditioning Amplifier Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D56-3 (CANH) - D56-14 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  5. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - AWD CONTROL ECU)

    Tech Tips

    For 2WD vehicles, go to the next step.


    1. A01EK6DE07
      Text in Illustration
      *1

      Front view of wire harness connector

      (to AWD Control ECU)

      Disconnect the AWD control ECU connector.

    2. A01EKZ3E49
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *3 to AWD Control ECU

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D56-11 (CANH) - D56-22 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  6. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C - POWER MANAGEMENT CONTROL ECU)

    Tech Tips

    For vehicles without smart entry and start system, go to the next step.


    1. A01ELA6E17
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the power management control ECU connector (D43).

    2. A01EKZ3E36
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *3 to Power Management Control ECU

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D56-10 (CANH) - D56-21 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  7. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 1 J/C)


    1. Reconnect the CAN No. 1 junction connectors (A44 and D56).

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Note

      The resistance must be measured after the main wire connected ECUs (ECM and combination meter assembly), and CAN No. 1 and No. 2 junction connectors are reconnected.

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  8. CHECK FOR SHORT IN CAN BUS WIRES (SKID CONTROL ECU (BRAKE ACTUATOR ASSEMBLY))


    1. Reconnect the skid control ECU (brake actuator assembly) connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (for AWD and w/o Smart entry and start system) A
      OK (for 2WD and w/o Smart entry and start system) B
      OK (for AWD and w/ Smart entry and start system) C
      OK (for 2WD and w/ Smart entry and start system) D
      NG E

    B
    C
    D
    E
    A
  9. CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER ASSEMBLY)


    1. Reconnect the air conditioning amplifier assembly connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  10. CHECK FOR SHORT IN CAN BUS WIRES (POWER MANAGEMENT CONTROL ECU)


    1. Reconnect the power management control ECU connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  11. CHECK FOR SHORT IN CAN BUS WIRES (ECM)


    1. A01EMIIE79
      Text in Illustration
      *1

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. A01EKZ3E91
      Text in Illustration
      *4

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *5 to ECM

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A44-4 (CANH) - A44-15 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  12. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - CAN NO. 1 J/C)


    1. Reconnect the CAN No. 1 junction connector (D56).

    2. A01EKZ3E37
      Text in Illustration
      *1

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *2 to CAN No. 1 Junction Connector

      Disconnect the CAN No. 2 junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-9 (CANH) - D68-20 (CANL) Ignition switch off 108 to 132 Ω

    NG
    OK
  13. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - DLC3)


    1. A01EKZ3E38
      Text in Illustration
      *1

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *2 to DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-6 (CANH) - D68-17 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  14. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - COMBINATION METER ASSEMBLY)


    1. A01EKZ3E46
      Text in Illustration
      *1

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *2 to Combination Meter Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-8 (CANH) - D68-19 (CANL) Ignition switch off 108 to 132 Ω

    NG
    OK
  15. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - CENTER AIRBAG SENSOR ASSEMBLY)


    1. A01EM09E08
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

      Disconnect the center airbag sensor assembly connector (D6).

    2. A01EKZ3E40
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Center Airbag Sensor Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-2 (CANH) - D68-13 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  16. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - YAW RATE AND ACCELERATION SENSOR)


    1. A01ELLGE09
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Yaw Rate and Acceleration Sensor)

      Disconnect the yaw rate and acceleration sensor connector.

    2. A01EKZ3E41
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Yaw Rate and Acceleration Sensor

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-3 (CANH) - D68-14 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  17. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - STEERING ANGLE SENSOR (SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY))


    1. A01ELYUE17
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Steering Angle Sensor (Spiral Cable with Sensor Sub-assembly))

      Disconnect the steering angle sensor (spiral cable with sensor sub-assembly) connector.

    2. A01EKZ3E42
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Steering Angle Sensor (Spiral Cable with Sensor Sub-assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-5 (CANH) - D68-16 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  18. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - POWER STEERING ECU ASSEMBLY)


    1. A01EJMFE05
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Power Steering ECU Assembly)

      Disconnect the power steering ECU assembly connector (D20).

    2. A01EKZ3E50
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Power Steering ECU Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-7 (CANH) - D68-18 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  19. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY))


    1. A01EMNWE10
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Main Body ECU (Driver Side Junction Block Assembly))

      Disconnect the main body ECU (driver side junction block assembly) connector (D48).

    2. A01EKZ3E43
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Main Body ECU (Driver Side Junction Block Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-4 (CANH) - D68-15 (CANL) Ignition switch off 1 MΩ or higher
      Result
      Result Proceed to
      OK (w/ Smart entry and start system) A
      OK (w/o Smart entry and start system) B
      NG C

    B
    C
    A
  20. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - CERTIFICATION ECU (SMART KEY ECU ASSEMBLY))


    1. A01EJ4DE16
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Certification ECU (Smart Key ECU Assembly))

      Disconnect the certification ECU (smart key ECU assembly) connector.

    2. A01EKZ3E44
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Certification ECU (Smart Key ECU Assembly)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-10 (CANH) - D68-21 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  21. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - NAVIGATION RECEIVER ASSEMBLY)

    Tech Tips

    The vehicle for radio and display type go to the next step.


    1. A01ELRIE50
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Navigation Receiver Assembly)

      Disconnect the navigation receiver assembly connector.

    2. A01EL64E17
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Navigation Receiver Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-11 (CANH) - D68-22 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  22. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C - RADIO AND DISPLAY RECEIVER ASSEMBLY)


    1. A01ELRIE60
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Radio and Display Receiver Assembly)

      Disconnect the radio and display receiver assembly connector.

    2. A01EL64E17
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Radio and Display Receiver Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-11 (CANH) - D68-22 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK
  23. CHECK FOR SHORT IN CAN BUS WIRES (CAN NO. 2 J/C)


    1. Reconnect the CAN No. 2 junction connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Note

      The resistance must be measured after the main wire connected ECUs (ECM and combination meter assembly), and CAN No. 1 and No. 2 junction connectors are reconnected.

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  24. CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR ASSEMBLY)


    1. Reconnect the center airbag sensor assembly connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  25. CHECK FOR SHORT IN CAN BUS WIRES (YAW RATE AND ACCELERATION SENSOR)


    1. Reconnect the yaw rate and acceleration sensor connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  26. CHECK FOR SHORT IN CAN BUS WIRES (STEERING ANGLE SENSOR (SPIRAL CABLE WITH SENSOR SUB-ASSEMBLY))


    1. Reconnect the steering angle sensor (spiral cable with sensor sub-assembly) connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  27. CHECK FOR SHORT IN CAN BUS WIRES (POWER STEERING ECU ASSEMBLY)


    1. Reconnect the power steering ECU assembly connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (for Navigation receiver type) A
      OK (for Radio and display type) B
      NG C

    B
    C
    A
  28. CHECK FOR SHORT IN CAN BUS WIRES (NAVIGATION RECEIVER ASSEMBLY)


    1. Reconnect the navigation receiver assembly connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (w/o Smart entry and start system) A
      OK (w/ Smart entry and start system) B
      NG (for Navigation receiver type) C

    B
    C
    A
  29. CHECK FOR SHORT IN CAN BUS WIRES (RADIO AND DISPLAY RECEIVER ASSEMBLY)


    1. Reconnect the radio and display receiver assembly connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω
      Result
      Result Proceed to
      OK (w/o Smart entry and start system) A
      OK (w/ Smart entry and start system) B
      NG C

    B
    C
    A
  30. CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU (DRIVER SIDE JUNCTION BLOCK ASSEMBLY))


    1. Reconnect the main body ECU (driver side junction block assembly) connector.

    2. A01EJIYE83
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D1-6 (CANH) - D1-14 (CANL) Ignition switch off 54 to 69 Ω

    NG
    OK
  31. CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ASSEMBLY)


    1. A01EMBVE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the combination meter assembly connector (E1).

    2. A01EKZ3E45
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *3 to Combination Meter Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D68-8 (CANH) - D68-19 (CANL) Ignition switch off 1 MΩ or higher

    NG
    OK