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 wires and +B when no resistance exists 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

  • No resistance exists 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.

  • No resistance exists between terminal 19 (CAYH) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 20 (CAYL) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

  • Short to GND in CAN main bus line

  • Short to GND in CAN branch line

  • Central gateway ECU (network gateway ECU)

  • Navigation receiver assembly (EMVN ECU)*1

  • Radio and display receiver assembly (EMVN ECU)*2

  • Telematics transceiver*3

  • Bus buffer ECU*4

  • No. 5 CAN junction connector
*1: w/ Navigation System
*2: w/ Audio and Visual System
*3: w/ Telematics Transceiver
*4: w/ Bus Buffer ECU

WIRING DIAGRAM

B001EBTE01

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 ignition 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 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.

    Click here

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here

  • 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 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 WIRE (NO. 5 CAN JUNCTION CONNECTOR)


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

    2. B001G4SC02
      *a

      Front view of wire harness connector

      (to No. 5 CAN Junction Connector)
      *b Front view of DLC3
      *c to Central Gateway ECU (Network Gateway ECU)
      *d to Central Gateway ECU (Network Gateway ECU)
      *e

      • to Navigation Receiver Assembly (EMVN ECU) (w/ Navigation System)

      • to Radio and Display Receiver Assembly (EMVN ECU) (w/ Audio and Visual System)
      *f to Telematics Transceiver (w/ Telematics Transceiver)
      *g to Bus Buffer ECU (w/ Bus Buffer ECU)

      Disconnect the No. 5 CAN junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G289-1 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      G289-12 (CANL) - G48-4 (CG)
      G289-2 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      G289-13 (CANL) - G48-4 (CG)
      G289-3 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Navigation receiver assembly (EMVN ECU)*1

      • Radio and display receiver assembly (EMVN ECU)*2
      G289-14 (CANL) - G48-4 (CG)
      G289-4 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Telematics transceiver*3
      G289-15 (CANL) - G48-4 (CG)
      G289-5 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Bus buffer ECU*4
      G289-16 (CANL) - G48-4 (CG)
      *1: w/ Navigation System
      *2: w/ Audio and Visual System
      *3: w/ Telematics Transceiver
      *4: w/ Bus Buffer ECU
      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU [network gateway ECU] CAN main wire) B
      NG (Wire to ECU or sensor) C

    A

    REPLACE NO. 5 CAN JUNCTION CONNECTOR

    C

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

    B

  2. CONNECT CONNECTOR


    1. Reconnect the G289 No. 5 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 5 CAN JUNCTION CONNECTOR)


    1. B001HSMC96
      *a

      Front view of wire harness connector

      (to Central Gateway ECU [Network Gateway ECU])
      *b Front view of DLC3

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G229-6 (CA3H) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G229-21 (CA3L) - G48-4 (CG)
      G229-19 (CAYH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G229-20 (CAYL) - G48-4 (CG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 5 CAN JUNCTION CONNECTOR - CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU])

  4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (ECU, SENSOR)


    1. Reconnect the wire harness connectors.

    2. B001DY4C38
      *a

      Component with harness connected

      (Central Gateway ECU [Network Gateway ECU])
      *b Front view of DLC3

      Disconnect the connector that includes terminals CANH and CANL from the ECU or sensor to which the short to GND is connected.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G229-6 (CA3H) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G229-21 (CA3L) - G48-4 (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 GND in the wire harness and repair or replace the wire harness or connector if necessary.

      Result
      Proceed to
      OK
      NG

    OK

    REPLACE ECU OR SENSOR

    NG

    REPLACE CORRESPONDING ECU OR SENSOR