CAN COMMUNICATION SYSTEM(w/ Central Gateway ECU) 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 line

  • Short to ground in CAN branch line

  • Central gateway ECU (network gateway ECU)

  • Radio and display receiver assembly

    (for Radio and Display Type)

  • Navigation receiver assembly

    (for Navigation Receiver Type)

  • No. 6 CAN junction connector

WIRING DIAGRAM

B005ZUHE11

CAUTION / NOTICE / HINT

CAUTION:

When performing the confirmation driving pattern, obey all speed limits and traffic laws.

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 or any 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) 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. 6 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the L204 No. 6 CAN junction connector.

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

      B005ZS2C72
      *1 DLC3 - -
      *a

      Front view of wire harness connector

      (to No. 6 CAN Junction Connector)

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

      to Radio and Display Receiver Assembly

      (for Radio and Display Type)

      *d

      to Navigation Receiver Assembly

      (for Navigation Receiver Type)

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L204-5 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      L204-16 (CANL) - L61-4 (CG)
      L204-6 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      L204-17 (CANL) - L61-4 (CG)
      L204-7 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Radio and display receiver assembly*1
      L204-18 (CANL) - L61-4 (CG)
      L204-7 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher Navigation receiver assembly*2
      L204-18 (CANL) - L61-4 (CG)

      • *1: for Radio and Display Type

      • *2: for Navigation Receiver Type

      Result
      Symptom 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. 6 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU))


    1. Disconnect the L192 central gateway ECU (network gateway ECU) connector.

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

      B005ZS2C73
      *1 DLC3 - -
      *a

      Front view of wire harness connector

      (to No. 6 CAN Junction Connector)

      *b to Central Gateway ECU (Network Gateway ECU)
      Standard Resistance
      Tester Connection Condition Specified Condition
      L204-5 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      L204-16 (CANL) - L61-4 (CG)
      L204-6 (CANH) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      L204-17 (CANL) - L61-4 (CG)

    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.

      B005YEPC85
      *1 DLC3 - -
      *a

      Component with harness connected

      (Central Gateway ECU (Network Gateway ECU))

      - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      L192-6 (CA3H) - L61-4 (CG) Cable disconnected from negative (-) auxiliary battery terminal 200 Ω or higher
      L192-21 (CA3L) - L61-4 (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.


    OK
    NG