CAN COMMUNICATION SYSTEM Check CAN Bus Line for Short to GND

DTC Code DTC Name
Check CAN Bus Line for Short to GND

DESCRIPTION

There may be a short circuit between one of the CAN bus lines 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 in CAN main bus line

  • Short in CAN branch line

  • Combination meter assembly

  • Power steering ECU assembly

  • Steering sensor (spiral cable sub-assembly)*1

  • Airbag sensor assembly

  • ECM

  • Skid control ECU (brake actuator assembly)

  • Certification ECU (smart key ECU assembly)*2

  • Engine stop and start ECU*3

  • Radio and display receiver assembly*4

  • Air conditioning control assembly*5

  • No. 1 CAN junction connector

  • *1: w/ VSC

  • *2: w/ Entry and Start System

  • *3: w/ Stop and Start System

  • *4: for Radio and Display Type

  • *5: for Automatic Air Conditioning System

WIRING DIAGRAM

C301058E01
C301059E01

CAUTION / NOTICE / HINT

Note:

  • 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 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.

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  • 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.

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  • 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 at least 31 seconds, and then drive the vehicle at a speed of 20 km/h (12 mph) or more for 8.42 seconds 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.

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Tip:

  • 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 TO GND IN CAN BUS LINE (NO. 1 CAN JUNCTION CONNECTOR (ENGINE ROOM MAIN WIRE))

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

    2. Disconnect the A59 No. 1 CAN junction connector.

      C289289C38

      *1

      DLC3

      -

      -

      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)

      *b

      to ECM

      *c

      to Skid Control ECU (Brake Actuator Assembly)

      *d

      to Engine Stop and Start ECU

      (w/ Stop and Start System)

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      Connected to

      A59-1 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      ECM

      A59-12 (CANL) - E8-4 (CG)

      A59-2 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Skid control ECU (brake actuator assembly)

      A59-13 (CANL) - E8-4 (CG)

      A59-3 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Engine stop and start ECU*

      A59-14 (CANL) - E8-4 (CG)

    *: w/ Stop and Start System

    Result

    Result

    Proceed to

    OK

    A

    NG (ECU or sensor bus line)

    B
    B

    CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU, SENSOR)Click here

    A

  2. CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 1 CAN JUNCTION CONNECTOR (INSTRUMENT PANEL WIRE))

    1. Disconnect the E2 No. 1 CAN junction connector.

      C289289C39

      *1

      DLC3

      -

      -

      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)

      *b

      to Airbag Sensor Assembly

      *c

      to Radio and Display Receiver Assembly

      (for Radio and Display Type)

      *d

      to Combination Meter Assembly

      *e

      to Air Conditioning Control Assembly

      (for Automatic Air Conditioning System)

      *f

      to Power Steering ECU Assembly

      *g

      to Steering Sensor (Spiral Cable Sub-assembly)

      (w/ VSC)

      *h

      to DLC3

      *i

      to Certification ECU (Smart Key ECU Assembly)

      (w/ Entry and Start System)

      -

      -

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      Connected to

      E2-1 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Airbag sensor assembly

      E2-12 (CANL) - E8-4 (CG)

      E2-2 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Radio and display receiver assembly*1

      E2-13 (CANL) - E8-4 (CG)

      E2-4 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Combination meter assembly

      E2-15 (CANL) - E8-4 (CG)

      E2-5 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Air conditioning control assembly*2

      E2-16 (CANL) - E8-4 (CG)

      E2-6 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Power steering ECU assembly

      E2-17 (CANL) - E8-4 (CG)

      E2-7 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Steering sensor (spiral cable sub-assembly)*3

      E2-18 (CANL) - E8-4 (CG)

      E2-8 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      DLC3

      E2-19 (CANL) - E8-4 (CG)

      E2-9 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      Certification ECU (smart key ECU assembly)*4

      E2-20 (CANL) - E8-4 (CG)

      • *1: for Radio and Display Type

      • *2: for Automatic Air Conditioning System

      • *3: w/ VSC

      • *4: w/ Entry and Start System

    Result

    Result

    Proceed to

    OK

    A

    NG (ECU or sensor bus line)

    B

    NG (DLC3 branch line)

    C
    A

    REPLACE NO. 1 CAN JUNCTION CONNECTOR

    C

    REPAIR OR REPLACE CAN BRANCH LINE CONNECTED TO DLC3

    B

  3. CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU, SENSOR)

    1. Reconnect all wire harness connectors.

    2. Disconnect the ECU or sensor connected to the CAN bus line that is shorted to ground.

      Tip:

      If the ECU or sensor has multiple connectors, disconnect the connector that includes the CAN bus lines. To determine the ECU or sensor that is connected to the shorted bus line, refer to Terminals of ECU.

      Click here

    3. C151827C66

      *1

      DLC3

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      E8-6 (CANH) - E8-4 (CG)

      Cable disconnected from negative (-) battery terminal

      200 Ω or higher

      E8-14 (CANL) - E8-4 (CG)
      Tip:

      If the resistance changes to 200 Ω or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.

    Result

    Result

    OK

    NG
    OK

    REPLACE CORRESPONDING ECU OR SENSOR

    NG

    REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR BUS LINE OR CONNECTOR