CAN COMMUNICATION SYSTEM(w/o Central Gateway ECU) 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 53 Ω.

Symptom Trouble Area
The resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is below 53 Ω.
  • Short in CAN main bus wire

  • Short in CAN branch wire

  • DLC3 CAN branch wire or connector

  • ECM

  • Brake actuator assembly (skid cotrol ECU)

  • 4 wheel drive control ECU

  • Airbag sensor assembly

  • Air conditioning amplifier assembly

  • Combination meter assembly

  • Main body ECU (multiplex network body ECU)

  • No. 1 CAN junction connector

  • No. 2 CAN junction connector*1

  • No. 3 CAN junction connector*1

  • No. 4 CAN junction connector*2

  • No. 5 CAN junction connector*1

  • No. 6 CAN junction connector*2

*1: for LHD
*2: for RHD

WIRING DIAGRAM


  1. for LHD

    B001H54E02
  2. for RHD

    B001FF1E01

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

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

  • Some parts must be initialized and set when replacing or removing and installing parts.

    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 for 1 minute or more. Then operate the suspected malfunctioning system and drive the vehicle at 60 km/h (37 mph) or more for 5 minutes 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 as normal.

    Click here

  • When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

  • Before replacing the certification ECU (smart key ECU assembly), refer to the entry and start system.

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


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

    2. Disconnect the No. 2 CAN junction connector.

      B001FLCC01
      *a

      Front view of wire harness connector

      (to No. 2 CAN Junction Connector)

      *b to No. 5 CAN Junction Connector
      *c to Airbag Sensor Assembly *d to No. 3 CAN Junction Connector
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G293-1 (CANH) - G293-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 5 CAN junction connector
      G293-5 (CANH) - G293-16 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Airbag sensor assembly
      G293-6 (CANH) - G293-17 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 3 CAN junction connector
      Result
      Result Proceed to
      OK A
      NG (No. 3 CAN junction connector CAN main wire) B
      NG (No. 5 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A
    C
    D
    B
  3. CONNECT CONNECTOR


    1. Reconnect the G293 No. 2 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  4. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 3 CAN junction connector.

      B001FTLC01
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)

      *b to No. 2 CAN Junction Connector
      *c to Combination Meter Assembly *d to Main Body ECU (Multiplex Network Body ECU)
      *e to DLC3 - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G294-1 (CANH) - G294-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 2 CAN junction connector
      G294-2 (CANH) - G294-13 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Combination meter assembly
      G294-3 (CANH) - G294-14 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Main body ECU (multiplex network body ECU)
      G294-5 (CANH) - G294-16 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher DLC3
      Result
      Result Proceed to
      OK A
      NG (Combination meter assembly CAN main wire) B
      NG (No. 2 CAN junction connector CAN main wire) C
      NG (DLC3 CAN branch wire) D
      NG (Wire to ECU or sensor) E

    A
    C
    D
    E
    B
  5. CONNECT CONNECTOR


    1. Reconnect the G294 No. 3 CAN junction connector.

      Result
      Proceed to
      NEXT

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


    1. B001GYBC18
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G6-40 (CANH) - G6-39 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK
    NG
  7. CONNECT CONNECTOR


    1. Reconnect the G293 No. 2 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  8. CHECK FOR SHORT IN CAN BUS WIRES (NO. 5 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 5 CAN junction connector.

      B001FLCC02
      *a

      Front view of wire harness connector

      (to No. 5 CAN Junction Connector)

      *b to No. 2 CAN Junction Connector
      *c to 4 Wheel Drive Control ECU *d to Air Conditioning Amplifier Assembly
      *e to No. 1 CAN Junction Connector - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G296-1 (CANH) - G296-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 2 CAN junction connector
      G296-2 (CANH) - G296-13 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher 4 wheel drive control ECU
      G296-4 (CANH) - G296-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Air conditioning amplifier assembly
      G296-6 (CANH) - G296-17 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction connector
      Result
      Result Proceed to
      OK A
      NG (No. 1 CAN junction connector CAN main wire) B
      NG (No. 2 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A
    C
    D
    B
  9. CONNECT CONNECTOR


    1. Reconnect the G296 No. 5 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  10. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 1 CAN junction connector.

      B001CM0C01
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)

      *b to No. 5 CAN Junction Connector
      *c to ECM *d to Brake Actuator Assembly (Skid Control ECU)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A119-9 (CANH) - A119-20 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 5 CAN junction connector
      A119-10 (CANH) - A119-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω ECM
      A119-11 (CANH) - A119-22 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Brake actuator assembly (skid control ECU)
      Result
      Result Proceed to
      OK A
      NG (ECM CAN main wire) B
      NG (No. 5 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A
    C
    D
    B
  11. CONNECT CONNECTOR


    1. Reconnect the A119 No. 1 CAN junction connector.

      Result
      Proceed to
      NEXT

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


    1. B001DOPC06
      *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 Condition Specified Condition
      G183-25 (CANH) - G183-31 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK
    NG
  13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 4 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the No. 4 CAN junction connector.

      B001FLCC03
      *a

      Front view of wire harness connector

      (to No. 4 CAN Junction Connector)

      *b to No. 6 CAN Junction Connector
      *c to Main Body ECU (Multiplex Network Body ECU) *d to DLC3
      *e to Airbag Sensor Assembly *f to No. 1 CAN Junction Connector
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G295-1 (CANH) - G295-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 6 CAN junction connector
      G295-2 (CANH) - G295-13 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Main body ECU (multiplex network body ECU)
      G295-4 (CANH) - G295-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher DLC3
      G295-5 (CANH) - G295-16 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Airbag sensor assembly
      G295-8 (CANH) - G295-19 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction connector
      Result
      Result Proceed to
      OK A
      NG (No. 1 CAN junction connector CAN main wire) B
      NG (No. 6 CAN junction connector CAN main wire) C
      NG (DLC3 CAN branch wire) D
      NG (Wire to ECU or sensor) E

    A
    C
    D
    E
    B
  14. CONNECT CONNECTOR


    1. Reconnect the G295 No. 4 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  15. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 1 CAN junction connector.

      B001CM0C01
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)

      *b to No. 4 CAN Junction Connector
      *c to Combination Meter Assembly *d to Brake Actuator Assembly (Skid Control ECU)
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A119-9 (CANH) - A119-20 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 4 CAN junction connector
      A119-10 (CANH) - A119-21 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Combination meter assembly
      A119-11 (CANH) - A119-22 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Brake actuator assembly (skid control ECU)
      Result
      Result Proceed to
      OK A
      NG (Combination meter assembly CAN main wire) B
      NG (No. 4 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A
    C
    D
    B
  16. CONNECT CONNECTOR


    1. Reconnect the A119 No. 1 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  17. CHECK FOR SHORT IN CAN BUS WIRES (COMBINATION METER ASSEMBLY - NO. 1 CAN JUNCTION CONNECTOR)


    1. B001GYBC18
      *a

      Front view of wire harness connector

      (to Combination Meter Assembly)

      Disconnect the combination meter assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G6-40 (CANH) - G6-39 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK
    NG
  18. CONNECT CONNECTOR


    1. Reconnect the G295 No. 4 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  19. CHECK FOR SHORT IN CAN BUS WIRES (NO. 6 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 6 CAN junction connector.

      B001FLCC04
      *a

      Front view of wire harness connector

      (to No. 6 CAN Junction Connector)

      *b to No. 4 CAN Junction Connector
      *c to ECM *d to 4 Wheel Drive Control ECU
      *e to Air Conditioning Amplifier Assembly - -
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G297-1 (CANH) - G297-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 4 CAN junction connector
      G297-2 (CANH) - G297-13 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω ECM
      G297-3 (CANH) - G297-14 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher 4 wheel drive control ECU
      G297-4 (CANH) - G297-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Air conditioning amplifier assembly
      Result
      Result Proceed to
      OK A
      NG (ECM CAN main wire) B
      NG (No. 4 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A
    C
    D
    B
  20. CONNECT CONNECTOR


    1. Reconnect the G297 No. 6 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT
  21. CHECK FOR SHORT IN CAN BUS WIRES (ECM - NO. 6 CAN JUNCTION CONNECTOR)


    1. B001DOPC06
      *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 Condition Specified Condition
      G183-25 (CANH) - G183-31 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK
    NG
  22. CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR)


    1. Reconnect all wire harness connectors.

    2. B001HH7C60
      *a Front view of DLC3

      Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the short circuited branch line is connected.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G48-6 (CANH) - G48-14 (CANL) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Tech Tips

      If the resistance becomes normal (between 54 and 69 Ω) when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.

      Result
      Proceed to
      OK
      NG

    OK
    NG