CAN COMMUNICATION SYSTEM(w/o Central Gateway ECU) Open in CAN Main Bus Line (RHD Models)

DESCRIPTION

There may be an open circuit in one of the V bus main lines and/or a DLC3 branch line when the resistance between terminals 6 (CANH) and 14 (CANL) of the DLC3 is 70 Ω or higher.

Symptom Trouble Area
Resistance between terminals 6 (CANH) and 14 (CANL) of DLC3 is 70 Ω or higher.
  • DLC3 branch line or connector

  • CAN main bus line or connector

  • ECM

  • Meter circuit plate

  • CAN No. 1 junction connector

  • CAN No. 2 junction connector

  • CAN No. 3 junction connector

This malfunction is not related to the lines of a CAN main bus branch or to ECUs or sensor connected a CAN main bus branch.

WIRING DIAGRAM

A005B3JE23

CAUTION / NOTICE / HINT

Note


  • Before measuring the resistance of the CAN bus, turn the power switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors. After that, disconnect the cable from the negative (-) auxiliary battery terminal and leave the vehicle for 1 minute or more before measuring the resistance.

  • After turning the power switch off, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Click here.

  • 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.

  • After performing repairs, perform the DTC check procedure and confirm that the DTCs are not output again.

  • DTC check procedure: Turn the power switch on (IG), turn the cruise control system on using the cruise control switch (ON/OFF switch), wait at least 60 seconds, and then drive the vehicle at a speed of 50 km/h (31 mph) or more for at least 1.72 seconds.

  • After the repair, perform CAN Bus Check and check that all the ECUs and sensors connected to the CAN communication system are displayed Click here.

Tech Tips


  • Operating the power 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 OPEN IN CAN BUS LINES (DLC3 BRANCH LINE)


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

    2. A005A0KE01
      Text in Illustration
      *1 DLC3

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L61-6 (CANH) - L61-14 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

      Note

      When the measured value is 133 Ω or higher and a CAN communication system DTC is output, there may be a fault besides disconnection of the DLC3 branch line. For that reason, troubleshooting should be performed again from How to Proceed with Troubleshooting after repairing the trouble area Click here.


    NG
    OK
  2. CHECK FOR OPEN IN CAN BUS LINES (ECM)


    1. A005DLLE01
      Text in Illustration
      *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
      A57-13 (CANH) - A57-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    OK
    NG
  3. CHECK FOR OPEN IN CAN BUS LINES (METER CIRCUIT PLATE)


    1. Reconnect the ECM connector.

    2. A005DJFE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Meter Circuit Plate)

      Disconnect the meter circuit plate connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L27-19 (CANH) - L27-20 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    OK
    NG
  4. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C)


    1. Reconnect the meter circuit plate connector.

    2. A005AYIE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 2 Junction Connector)

      *b to CAN No. 1 Junction Connector
      *c to CAN No. 3 Junction Connector

      Disconnect the wire harness connector from the CAN No. 2 junction connector (instrument panel connector holder left side).

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L94-1 (CANH) -L94-2 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 1 junction connector
      L94-4 (CANH) - L94-5 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 3 junction connector
      Result
      Result Proceed to
      OK A
      NG (CAN No. 3 junction connector main line) B
      NG (CAN No. 1 junction connector main line) C

    A
    C
    B
  5. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 2 J/C - CAN NO. 3 J/C)


    1. Reconnect the wire harness connector to the CAN No. 2 junction connector (instrument panel connector holder left side).

    2. A005A26E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)

      *b to CAN No. 2 Junction Connector

      Disconnect the wire harness connector from the CAN No. 3 junction connector (instrument panel wire side).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L133-6 (CANH) - L133-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    NG
    OK
  6. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 3 J/C - ECM)


    1. A005BY1E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 3 Junction Connector)

      *b to ECM

      Disconnect the wire harness connector from the CAN No. 3 junction connector (engine room main wire side).

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      A68-1 (CANH) - A68-7 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω

    OK
    NG
  7. CHECK FOR OPEN IN CAN BUS LINES (CAN NO. 1 J/C)


    1. Reconnect the wire harness connector to the CAN No. 2 junction connector (instrument panel connector holder left side).

    2. A005BQWE02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to CAN No. 1 Junction Connector)

      *b to CAN No. 2 Junction Connector
      *c to Meter Circuit Plate

      Disconnect the wire harness connector from the CAN No. 1 junction connector (instrument panel wire side).

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L132-5 (CANH) -L132-11 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω CAN No. 2 junction connector
      L132-6 (CANH) - L132-12 (CANL) Cable disconnected from negative (-) auxiliary battery terminal 108 to 132 Ω Meter circuit plate
      Result
      Result Proceed to
      OK A
      NG (CAN No. 2 junction connector main line) B
      NG (Meter circuit plate main line) C

    A
    B
    C