CAN COMMUNICATION SYSTEM Check CAN Bus Line for Short to GND (LHD Models)

DESCRIPTION

There may be a short circuit between the CAN bus line and GND when there is no resistance between terminals 6 (CANH) and 4 (CG) or terminals 14 (CANL) and 4 (CG) of the DLC3.

Symptom Trouble Area
No resistance exists between terminals 6 (CANH) and 4 (CG) or terminals 14 (CANL) and 4 (CG) of DLC3.

  • Short to GND in CAN bus wire

  • Skid control ECU

  • Power steering ECU

  • Steering angle sensor

  • Yaw rate sensor

  • ECM

  • Center airbag sensor assembly

  • Air conditioning amplifier

  • Combination meter ECU

  • Main body ECU

  • Television camera ECU

  • CAN junction connector CTR

  • CAN junction connector RH

WIRING DIAGRAM

A017FYHE04
A017BDBE03

INSPECTION PROCEDURE

Note


  • Turn the ignition switch off before measuring the resistances of the CAN main wire and the CAN branch wire.

  • After the ignition switch is turned off, check that the key reminder warning system and light reminder warning system are not in operation.

  • 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 the doors need to be opened in order to check the connectors, open the doors and leave them open.

Tech Tips


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

  • 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 will help determine the cause of the malfunction.

PROCEDURE


  1. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)


    1. Turn the ignition switch off.

    2. Disconnect the CAN junction connector CTR.

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

      A017BAHE17
      Standard resistance
      Tester Connection Wiring Color Connect to Condition Specified Condition
      D47-1 (CANH) - D43-4 (CG) SB - B CAN junction connector RH Ignition switch off 200 Ω or higher
      D47-12 (CANL) - D43-4 (CG) W - B CAN junction connector RH Ignition switch off 200 Ω or higher
      D47-4 (CANH) - D43-4 (CG) L - B DLC3 Ignition switch off 200 Ω or higher
      D47-15 (CANL) - D43-4 (CG) W - B DLC3 Ignition switch off 200 Ω or higher
      D47-6 (CANH) - D43-4 (CG) P - B Combination meter Ignition switch off 200 Ω or higher
      D47-17 (CANL) - D43-4 (CG) W - B Combination meter Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      OK A
      NG (DLC3 branch wire) B
      NG (Combination meter main wire) C
      NG (CAN junction connector RH main wire) D

    B

    REPAIR OR REPLACE DLC3 BRANCH WIRE

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (COMBINATION METER MAIN WIRE) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH) Click here

    A

  2. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)


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

      A017BAHE18
      Standard resistance
      Tester Connection Wiring Color Connect to Condition Specified Condition
      D47-2 (CANH) - D43-4 (CG) V - B Yaw rate sensor Ignition switch off 200 Ω or higher
      D47-13 (CANL) - D43-4 (CG) W - B Yaw rate sensor Ignition switch off 200 Ω or higher
      D47-3 (CANH) - D43-4 (CG) Y - B Center airbag sensor assembly Ignition switch off 200 Ω or higher
      D47-14 (CANL) - D43-4 (CG) W - B Center airbag sensor assembly Ignition switch off 200 Ω or higher
      D47-5 (CANH) - D43-4 (CG) R- B Steering angle sensor Ignition switch off 200 Ω or higher
      D47-16 (CANL) - D43-4 (CG) W - B Steering angle sensor Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      OK A
      NG (Yaw rate sensor branch wire) B
      NG (Center airbag sensor assembly branch wire) C
      NG (Steering angle sensor branch wire) D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (STEERING ANGLE SENSOR BRANCH WIRE) Click here

    A

  3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR CTR)


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

      A017BAHE19
      Standard resistance
      Tester Connection Wiring Color Connect to Condition Specified Condition
      D47-7 (CANH) - D43-4 (CG) BR - B Power steering ECU Ignition switch off 200 Ω or higher
      D47-18 (CANL) - D43-4 (CG) W - B Power steering ECU Ignition switch off 200 Ω or higher
      D47-8 (CANH) - D43-4 (CG) GR - B Main body ECU Ignition switch off 200 Ω or higher
      D47-19 (CANL) - D43-4 (CG) W - B Main body ECU Ignition switch off 200 Ω or higher
      D47-9 (CANH) - D43-4 (CG) SB - B Television camera ECU Ignition switch off 200 Ω or higher
      D47-20 (CANL) - D43-4 (CG) W - B Television camera ECU Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      OK A
      NG (Power steering ECU branch wire) B
      NG (Main body ECU branch wire) C
      NG (Television camera ECU branch wire) D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (MAIN BODY ECU BRANCH WIRE) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (TELEVISION CAMERA ECU BRANCH WIRE) Click here

    A

    REPLACE CAN JUNCTION CONNECTOR CTR

  4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (COMBINATION METER MAIN WIRE)


    1. A017BD2E21

      Disconnect the combination meter connector.

    2. A017E4AE15

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-6 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-17 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (COMBINATION METER MAIN WIRE)

    OK

    REPLACE COMBINATION METER Click here

  5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH)


    1. Disconnect the CAN junction connector RH.

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

      A017BAHE20

      Tech Tips

      The resistance must be measured after the CAN junction connector CTR is disconnected.

      Standard resistance
      Tester Connection Wiring Color Connect to Condition Specified Condition
      D51-1 (CANH) - D43-4 (CG) R - B ECM Ignition switch off 200 Ω or higher
      D51-12 (CANL) - D43-4 (CG) W - B ECM Ignition switch off 200 Ω or higher
      D51-5 (CANH) - D43-4 (CG) SB - B CAN junction connector CTR Ignition switch off 200 Ω or higher
      D51-16 (CANL) - D43-4 (CG) W - B CAN junction connector CTR Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      OK A
      NG (ECM main wire) B
      NG (CAN junction connector CTR main wire) C

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM MAIN WIRE) Click here

    C

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN JUNCTION CONNECTOR - CAN JUNCTION CONNECTOR RH)

    A

  6. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN JUNCTION CONNECTOR RH)


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

      A017BAHE21
      Standard resistance
      Tester Connection Wiring Color Connect to Condition Specified Condition
      D51-3 (CANH) - D43-4 (CG) LG - B Air conditioning amplifier Ignition switch off 200 Ω or higher
      D51-14 (CANL) - D43-4 (CG) W - B Air conditioning amplifier Ignition switch off 200 Ω or higher
      D51-4 (CANH) - D43-4 (CG) B - B Skid control ECU Ignition switch off 200 Ω or higher
      D51-15 (CANL) - D43-4 (CG) W - B Skid control ECU Ignition switch off 200 Ω or higher
      Result
      Result Proceed to
      OK A
      NG (Air conditioning amplifier branch wire) B
      NG (Skid control ECU branch wire) C

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER BRANCH WIRE) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU BRANCH WIRE) Click here

    A

    REPLACE CAN JUNCTION CONNECTOR RH

  7. CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECM MAIN WIRE)


    1. A017EELE04

      Disconnect the ECM connector.

    2. A017E4AE16

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D51-1 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D51-12 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (ECM MAIN WIRE)

    OK

    REPLACE ECM Click here

  8. CHECK FOR SHORT TO GND IN CAN BUS WIRE (YAW RATE SENSOR BRANCH WIRE)


    1. A017DEAE04

      Disconnect the yaw rate sensor connector.

    2. A017E4AE39

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-2 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-13 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (YAW RATE SENSOR BRANCH WIRE)

    OK

    REPLACE YAW RATE SENSOR Click here

  9. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)


    1. A017DMZE22

      Disconnect the center airbag sensor assembly connector.

    2. A017E4AE28

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-3 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-14 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CENTER AIRBAG SENSOR ASSEMBLY BRANCH WIRE)

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here

  10. CHECK FOR SHORT TO GND IN CAN BUS WIRE (STEERING ANGLE SENSOR BRANCH WIRE)


    1. A017FNVE03

      Disconnect the steering angle sensor connector.

    2. A017E4AE35

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-5 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-16 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (STEERING ANGLE SENSOR BRANCH WIRE)

    OK

    REPLACE STEERING ANGLE SENSOR Click here

  11. CHECK FOR SHORT TO GND IN CAN BUS WIRE (POWER STEERING ECU BRANCH WIRE)


    1. A017BE3E11

      Disconnect the power steering ECU connector.

    2. A017E4AE19

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-7 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-18 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (POWER STEERING ECU BRANCH WIRE)

    OK

    REPLACE POWER STEERING ECU Click here

  12. CHECK FOR SHORT TO GND IN CAN BUS WIRE (MAIN BODY ECU BRANCH WIRE)


    1. A017F33E05

      Disconnect the main body ECU connector.

    2. A017E4AE20

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-8 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-19 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (MAIN BODY ECU BRANCH WIRE)

    OK

    REPLACE MAIN BODY ECU

  13. CHECK FOR SHORT TO GND IN CAN BUS WIRE (TELEVISION CAMERA ECU BRANCH WIRE)


    1. A017CLDE01

      Disconnect the television camera ECU connector.

    2. A017E4AE23

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D47-9 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D47-20 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (TELEVISION CAMERA ECU BRANCH WIRE)

    OK

    REPLACE PARKING ASSIST ECU (TELEVISION CAMERA ECU)

  14. CHECK FOR SHORT TO GND IN CAN BUS WIRE (AIR CONDITIONING AMPLIFIER BRANCH WIRE)


    1. A017FS6E06

      Disconnect the air conditioning amplifier connector.

    2. A017E4AE21

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D51-3 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D51-14 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (AIR CONDITIONING AMPLIFIER BRANCH WIRE)

    OK

    REPLACE AIR CONDITIONING AMPLIFIER Click here

  15. CHECK FOR SHORT TO GND IN CAN BUS WIRE (SKID CONTROL ECU BRANCH WIRE)


    1. A017C50E48

      Disconnect the skid control ECU connector.

    2. A017E4AE33

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

      Standard resistance
      Tester Connection Condition Specified Condition
      D51-4 (CANH) - D43-4 (CG) Ignition switch off 200 Ω or higher
      D51-15 (CANL) - D43-4 (CG) Ignition switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (SKID CONTROL ECU BRANCH WIRE)

    OK

    REPLACE BRAKE ACTUATOR ASSEMBLY Click here