CAN COMMUNICATION SYSTEM(for RHD) Check Bus 3 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 terminal 6 (CA3H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Symptom Trouble Area
There is no resistance between terminal 6 (CA3H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.
  • Short to ground in CAN main bus lines

  • Short to ground in CAN branch lines

  • Central gateway ECU (network gateway ECU)

  • Optional navigation receiver

    (w/ Optional Navigation Receiver)

  • Navigation receiver assembly

    (w/ Genuine Navigation Receiver)

  • No. 7 CAN junction connector

WIRING DIAGRAM

B006MRHE01

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 engine 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 engine 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

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

    DTC check procedure: Turn the engine switch on (IG) 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

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 FOR SHORT TO GND IN CAN BUS LINE (NO. 7 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the G130, G131 and G133 No. 7 CAN junction connectors.

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

      B006LTEC02
      *1 DLC3 - -
      *a

      Rear view of wire harness connector

      (to No. 7 CAN junction connector)

      *b to Central Gateway ECU (Network Gateway ECU)
      *c

      to Navigation Receiver Assembly

      (w/ Genuine Navigation Receiver)

      *d

      to Optional Navigation Receiver

      (w/ Optional Navigation Receiver)

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G130-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      G130-2 (CANL) - G9-4 (CG)
      G131-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      G131-2 (CANL) - G9-4 (CG)
      G133-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Navigation receiver assembly*1
      G133-2 (CANL) - G9-4 (CG)
      G133-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Optional navigation receiver*2
      G133-2 (CANL) - G9-4 (CG)

      • *1: w/ Genuine Navigation Receiver

      • *2: w/ Optional Navigation Receiver

      Note


      • Before disconnecting the connectors, make a note of where they are connected.

      • Reconnect each connector to its original position.

      Tech Tips

      If there is a short in a CAN bus line without any CAN compatible optional devices connected to the option connector, repair or replace the CAN bus branch line or the option connector.

      Result
      Result Proceed to
      OK A
      NG (Line to central gateway ECU (network gateway ECU)) B
      NG (Line to ECU or sensor) C

    A
    C
    B
  2. CHECK FOR SHORT TO GND IN CAN BUS LINE (NO. 7 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))


    1. Reconnect the G133 No. 7 CAN junction connector.

    2. Disconnect the G116 central gateway ECU (network gateway ECU) connector.

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

      B006QSTC02
      *1 DLC3 - -
      *a

      Rear view of wire harness connector

      (to No. 7 CAN Junction Connector)

      *b to Central Gateway ECU (Network Gateway ECU)
      Standard Resistance
      Tester Connection Condition Specified Condition
      G130-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G130-2 (CANL) - G9-4 (CG)
      G131-1 (CANH) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G131-2 (CANL) - G9-4 (CG)

      Note


      • Before disconnecting the connectors, make a note of where they are connected.

      • Reconnect each connector to its original position.

      Result
      Result
      OK
      NG

    OK
    NG
  3. CHECK FOR SHORT TO GND IN CAN BUS LINE (ECU OR SENSOR)


    1. Reconnect all wire harness connectors.

    2. Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the bus line shorted to GND is connected.

      Click here

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

      B006M71C42
      *1 DLC3 - -
      *a

      Component with harness connected

      (Central Gateway ECU (Network Gateway ECU))

      - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      G116-6 (CA3H) - G9-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G116-21 (CA3L) - G9-4 (CG)

      Tech Tips


      • 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.

      • If the resistance does not become normal when the connector is disconnected from the ECU or sensor, check for a short to ground in the wire harness and repair or replace the wire harness or connector if necessary.

      Result
      Result
      OK
      NG

    OK
    NG