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

DESCRIPTION

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

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

  • Short to GND in CAN bus main wire

  • Short to GND in CAN bus branch wire

  • ECM

  • Certification ECU (Smart key ECU)

  • Combination meter

  • Power steering ECU

  • Center airbag sensor assembly

  • Skid control ECU (Brake actuator assembly)

  • Steering angle sensor

  • Yaw rate sensor

  • Main body ECU (Multiplex network body ECU)

  • Power management control ECU

  • Multi-media module receiver assembly*1

  • Radio receiver assembly*2

  • CAN No. 1 junction connector

  • CAN No. 2 junction connector

WIRING DIAGRAM

A019LM4E01
A019LN2E03

INSPECTION PROCEDURE

Note


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

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

  • After the engine 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 1minute and do not operate the engine 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 engine 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 TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - CAN NO. 2 J/C)


    1. Turn the engine switch off.

    2. A019M7SE62
      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.

    3. A019K7ZE02
      Text in Illustration
      *3 DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F17-6 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F17-14 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - CAN NO. 1 J/C) Click here

    OK

  2. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C)

    A019L1GE53

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      F70-1 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Power steering ECU
      F70-12 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-2 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Steering angle sensor
      F70-13 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-3 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher DLC3
      F70-14 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Text in Illustration
      *1 Front view of wire harness connector (to CAN No. 1 Junction Connector)
      *2 DLC3
      *3 to Power Steering ECU
      *4 to Steering Angle Sensor
      *5 to DLC3
      Result
      Result Proceed to
      OK A
      NG (Power steering ECU branch wire) B
      NG (Steering angle sensor branch wire) C
      NG (DLC3 branch wire) D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - POWER STEERING ECU) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - STEERING ANGLE SENSOR) Click here

    D

    REPAIR OR REPLACE CAN BRANCH WIRE CONNECTED TO DLC3 (CAN NO. 1 J/C - DLC3)

    A

  3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C)

    A019L1GE54

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      F70-4 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Combination meter
      F70-15 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-5 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Main body ECU
      F70-16 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-6 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher ECM
      F70-17 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Text in Illustration
      *1 Front view of wire harness connector (to CAN No. 1 Junction Connector)
      *2 DLC3
      *3 to Combination Meter
      *4 to Main Body ECU
      *5 to ECM
      Result
      Result Proceed to
      OK A
      NG (Combination meter branch wire) B
      NG (Main body ECU branch wire) C
      NG (ECM main wire) D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - COMBINATION METER) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - MAIN BODY ECU) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - ECM) Click here

    A

  4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C)

    A019L1GE55

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      F70-9 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Power management control ECU
      F70-20 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-10 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Center airbag sensor assembly
      F70-21 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-11 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Yaw rate sensor
      F70-22 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Text in Illustration
      *1 Front view of wire harness connector (to CAN No. 1 Junction Connector)
      *2 DLC3
      *3 to Power Management Control ECU
      *4 to Center Airbag Sensor Assembly
      *5 to Yaw Rate Sensor
      Result
      Result Proceed to
      OK A
      NG (Power management control ECU branch wire) B
      NG (Center airbag sensor assembly branch wire) C
      NG (Yaw rate sensor branch wire) D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - POWER MANAGEMENT CONTROL ECU) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - CENTER AIRBAG SENSOR ASSEMBLY) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - YAW RATE SENSOR) Click here

    A

    REPLACE CAN NO. 1 JUNCTION CONNECTOR

  5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - CAN NO. 1 J/C)


    1. A019M7SE74
      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.

    2. A019K7ZE02
      Text in Illustration
      *3 DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F17-6 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F17-14 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

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

    OK

  6. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C)

    A019L1GE56

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      F71-1 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Skid control ECU
      F71-12 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F71-2 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher Certification ECU
      F71-13 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      F71-8 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher

      • Multi-media module receiver assembly

      • Radio receiver assembly
      F71-19 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Text in Illustration
      *1 Front view of wire harness connector (to CAN No. 2 Junction Connector)
      *2 DLC3
      *3 to Skid Control ECU
      *4 to Certification ECU
      *5

      • to Multi-media Module Receiver Assembly

      • to Radio Receiver Assembly
      Result
      Result Proceed to
      OK A
      NG (Skid Control ECU branch wire) B
      NG (Certification ECU main wire) C

      • NG (Multi-media module receiver assembly branch wire)

      • NG (Radio receiver assembly branch wire)

      		 D

    B

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - SKID CONTROL ECU) Click here

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - CERTIFICATION ECU) Click here

    D

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - MULTI-MEDIA MODULE OR RADIO RECEIVER) Click here

    A

    REPLACE CAN NO. 2 JUNCTION CONNECTOR

  7. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - POWER STEERING ECU)


    1. A019OZNE09
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Power Steering ECU)

      Disconnect the power steering ECU connector.

    2. A019O1ZE67
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Power Steering ECU

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-1 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-12 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - POWER STEERING ECU)

    OK

    REPLACE POWER STEERING ECU

  8. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - STEERING ANGLE SENSOR)


    1. A019MNQE27
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Steering Angle Sensor)

      Disconnect the steering angle sensor connector.

    2. A019O1ZE68
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Steering Angle Sensor

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-2 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-13 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - STEERING ANGLE SENSOR)

    OK

    REPLACE SPIRAL CABLE W/STEERING SENSOR SUB-ASSEMBLY

  9. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - COMBINATION METER)


    1. A019NZDE03
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter)

      Disconnect the combination meter connector.

    2. A019O1ZE69
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Combination Meter

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-4 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-15 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - COMBINATION METER)

    OK

    REPLACE COMBINATION METER ASSEMBLY

  10. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - MAIN BODY ECU)


    1. A019O5VE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Main Body ECU)

      Disconnect the main body ECU connector.

    2. A019O1ZE70
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Main Body ECU

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-5 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-16 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - MAIN BODY ECU)

    OK

    REPLACE MULTIPLEX NETWORK BODY ECU (MAIN BODY ECU)

  11. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - ECM)


    1. A019OJ1E52
      Text in Illustration
      *A for 2GR-FE
      *B for 1AR-FE
      *1

      Front view of wire harness connector

      (to ECM)

      Disconnect the ECM connector.

    2. A019O1ZE71
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to ECM

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-6 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-17 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Result
      Result Proceed to
      OK (for 2GR-FE) A
      OK (for 1AR-FE) B
      NG C

    B

    REPLACE ECM Click here

    C

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

    A

    REPLACE ECM Click here

  12. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - POWER MANAGEMENT CONTROL ECU)


    1. A019M6TE26
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to Power Management Control ECU)

      Disconnect the power management control ECU connector.

    2. A019O1ZE72
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Power Management Control ECU

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-9 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-20 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - POWER MANAGEMENT CONTROL ECU)

    OK

    REPLACE POWER MANAGEMENT CONTROL ECU

  13. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - CENTER AIRBAG SENSOR ASSEMBLY)


    1. A019O0VE11
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

      Disconnect the center airbag sensor assembly connector.

    2. A019O1ZE73
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Center Airbag Sensor Assembly

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-10 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-21 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - CENTER AIRBAG SENSOR ASSEMBLY)

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY

  14. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 1 J/C - YAW RATE SENSOR)


    1. A019KM6E11
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Yaw Rate Sensor)

      Disconnect the yaw rate sensor connector.

    2. A019O1ZE74
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)
      *3 DLC3
      *4 to Yaw Rate Sensor

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F70-11 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F70-22 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 1 J/C - YAW RATE SENSOR)

    OK

    REPLACE YAW RATE SENSOR ASSEMBLY

  15. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - SKID CONTROL ECU)


    1. A019MT5E01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Skid Control ECU)

      Disconnect the skid control ECU connector.

    2. A019O1ZE75
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)
      *3 DLC3
      *4 to Skid Control ECU

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F71-1 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F71-12 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 2 J/C- SKID CONTROL ECU)

    OK

    REPLACE BRAKE ACTUATOR (SKID CONTROL ECU)

  16. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - CERTIFICATION ECU)


    1. A019N51E06
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Certification ECU)

      Disconnect the certification ECU connector.

    2. A019O1ZE76
      Text in Illustration
      *2

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)
      *3 DLC3
      *4 to Certification ECU

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F71-2 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F71-13 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CAN NO. 2 JUNCTION CONNECTOR - CERTIFICATION ECU)

    OK

    REPLACE SMART KEY ECU ASSEMBLY (CERTIFICATION ECU)

  17. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CAN NO. 2 J/C - MULTI-MEDIA MODULE OR RADIO RECEIVER)


    1. w/ Navigation system


      1. A019MXHE14
        Text in Illustration
        *1

        Front view of wire harness connector

        (to Multi-media Module Receiver Assembly)

        Disconnect the multi-media module receiver assembly connector.

    2. w/ Audio and visual system (w/ Multi-display)


      1. A019PE7E03
        Text in Illustration
        *2

        Front view of wire harness connector

        (to Radio Receiver Assembly)

        Disconnect the radio receiver assembly connector.

    3. A019N3IE03
      Text in Illustration
      *3

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)
      *4 DLC3
      *5

      • to Multi-media Module Receiver Assembly

      • to Radio Receiver Assembly

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      F71-8 (CANH) - F17-4 (CG) Engine switch off 200 Ω or higher
      F71-19 (CANL) - F17-4 (CG) Engine switch off 200 Ω or higher
      Result
      Result Proceed to
      OK (w/ Navigation system) A
      OK (w/ Audio and visual system (w/ Multi-display)) B
      NG C

    B

    REPLACE RADIO RECEIVER ASSEMBLY (W/ AUDIO AND VISUAL SYSTEM (W/ MULTI-DISPLAY))

    C

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CAN NO. 2 J/C - MULTI-MEDIA MODULE OR RADIO RECEIVER)

    A

    REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY (W/ NAVIGATION SYSTEM)