CAN COMMUNICATION SYSTEM (for LHD) Short in CAN Bus Lines

DESCRIPTION

There may be a short circuit between the CAN bus lines 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 the DLC3 is below 54 Ω.

  • Short between CAN bus lines

  • ECM

  • Center airbag sensor assembly

  • Multi-media module receiver assembly

  • Headlight swivel ECU assembly (AFS ECU)

  • Air conditioning amplifier assembly

  • Network gateway ECU

  • Main body ECU (cowl side junction block LH)

  • Combination meter assembly

  • No. 1 junction connector

  • No. 2 junction connector

  • No. 3 junction connector

WIRING DIAGRAM

A01ERKGE01
A01EMU6E04

INSPECTION PROCEDURE

Note

The vehicle is equipped with an SRS (Supplemental Restraint System) which includes components such as airbags. Before servicing (including removal or installation of parts), be sure to read the Precaution in the SRS Click here.

Tech Tips

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

PROCEDURE


  1. PRECAUTION

    Note

    After turning the engine 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.


    NEXT

  2. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.


    NEXT

  3. CHECK FOR SHORT IN CAN BUS WIRES (DLC3 BRANCH WIRE)


    1. A01ER7DE04
      Text in Illustration
      *1 DLC3

      Disconnect the E75 No. 3 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E22-6 (CANH) - E22-14 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CANH, CANL)

    OK

  4. CONNECT CONNECTOR


    1. Reconnect the E75 No. 3 junction connector.


    NEXT

  5. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR SIDE)


    1. A01ER7DE04
      Text in Illustration
      *1 DLC3

      Disconnect the E72 No. 1 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E22-6 (CANH) - E22-14 (CANL) Engine switch off 108 to 132 Ω

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR) Click here

    OK

  6. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - CENTER AIRBAG SENSOR)


    1. A01EOQOE21
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-4 (CANH) - E72-15 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR) Click here

    OK

  7. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - AFS ECU)


    1. A01EOQOE30
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-3 (CANH) - E72-14 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (AFS ECU) Click here

    OK

  8. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 JUNCTION CONNECTOR - ECM)


    1. A01EOQOE22
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-2 (CANH) - E72-13 (CANL) Engine switch off 108 to 132 Ω

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (ECM) Click here

    OK

    REPLACE NO. 1 JUNCTION CONNECTOR

  9. CHECK FOR SHORT IN CAN BUS WIRES (CENTER AIRBAG SENSOR)


    1. A01EOQOE21
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      Disconnect the E47 center airbag sensor connector Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-4 (CANH) - E72-15 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO CENTER AIRBAG SENSOR (CANH, CANL)

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here

  10. CHECK FOR SHORT IN CAN BUS WIRES (AFS ECU)

    A01EOQOE30
    Text in Illustration
    *1

    Rear view of wire harness connector

    (to No. 1 Junction Connector)

    1. Disconnect the E91 headlight swivel ECU assembly (AFS ECU) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-3 (CANH) - E72-14 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AFS ECU (CANH, CANL)

    OK

    REPLACE HEADLIGHT SWIVEL ECU ASSEMBLY (AFS ECU) Click here

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


    1. A01EOQOE22
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 1 Junction Connector)

      Disconnect the A38 ECM connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E72-2 (CANH) - E72-13 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO ECM (CANH, CANL)

    OK

    REPLACE ECM Click here

  12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NO. 1 JUNCTION CONNECTOR)


    1. A01EOQOE23
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      Disconnect the E69 No. 2 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-1 (CANH) - E69-12 (CANL) Engine switch off 200 Ω or higher

    NG

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

    OK

  13. CONNECT CONNECTOR


    1. Reconnect the E72 No. 1 junction connector.


    NEXT

  14. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR SIDE)

    A01ER7DE04
    Text in Illustration
    *1 DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E22-6 (CANH) - E22-14 (CANL) Engine switch off 108 to 132 Ω

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR) Click here

    OK

  15. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - MULTI-MEDIA MODULE RECEIVER ASSEMBLY)


    1. A01EOQOE24
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-2 (CANH) - E69-13 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (MULTI-MEDIA MODULE RECEIVER ASSEMBLY) Click here

    OK

  16. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - AIR CONDITIONING AMPLIFIER)


    1. A01EOQOE25
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-5 (CANH) - E69-16 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER) Click here

    OK

  17. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)


    1. A01EOQOE26
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-3 (CANH) - E69-14 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU) Click here

    OK

    REPLACE NO. 2 JUNCTION CONNECTOR

  18. CHECK FOR SHORT IN CAN BUS WIRES (MULTI-MEDIA MODULE RECEIVER ASSEMBLY)


    1. A01EOQOE24
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      Disconnect the F76 multi-media module receiver assembly connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-2 (CANH) - E69-13 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MULTI-MEDIA MODULE RECEIVER ASSEMBLY (CANH, CANL)

    OK

    REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY Click here

  19. CHECK FOR SHORT IN CAN BUS WIRES (AIR CONDITIONING AMPLIFIER)


    1. A01EOQOE25
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      Disconnect the E35 air conditioning amplifier connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-5 (CANH) - E69-16 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO AIR CONDITIONING AMPLIFIER (CANH, CANL)

    OK

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

  20. CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)


    1. A01EOQOE26
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      Disconnect the E31 network gateway ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E69-3 (CANH) - E69-14 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO NETWORK GATEWAY ECU (CANH, CANL)

    OK

    REPLACE NETWORK GATEWAY ECU Click here

  21. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)


    1. A01EOQOE27
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 3 Junction Connector)

      Disconnect the E75 No. 3 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E75-1 (CANH) - E75-12 (CANL) Engine switch off 200 Ω or higher

    NG

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

    OK

  22. CONNECT CONNECTOR


    1. Reconnect the E69 No. 2 junction connector.


    NEXT

  23. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - MAIN BODY ECU)


    1. A01EOQOE28
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 3 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E75-4 (CANH) - E75-15 (CANL) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU) Click here

    OK

  24. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 JUNCTION CONNECTOR - COMBINATION METER)


    1. A01EOQOE29
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 3 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E75-3 (CANH) - E75-14 (CANL) Engine switch off 108 to 132 Ω

    NG

    CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER) Click here

    OK

    REPLACE NO. 3 JUNCTION CONNECTOR

  25. CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)


    1. A01EOQOE28
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 3 Junction Connector)

      Disconnect the E3 main body ECU (cowl side junction block LH) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E75-4 (CANH) - E75-15 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO MAIN BODY ECU (CANH, CANL)

    OK

    REPLACE MAIN BODY ECU (COWL SIDE JUNCTION BLOCK LH)

  26. CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER)


    1. A01EOQOE29
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to No. 3 Junction Connector)

      Disconnect the E77 combination meter connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      E75-3 (CANH) - E75-14 (CANL) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN MAIN WIRE CONNECTED TO COMBINATION METER (CANH, CANL)

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here