CAN COMMUNICATION SYSTEM(for RHD with Central Gateway ECU) Check Bus 3 Line for Short to +B

DESCRIPTION

There may be a short circuit between one of the CAN bus lines and +B when no resistance exists between terminal 6 (CA3H) of the central gateway ECU and terminal 16 (BAT) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU and terminal 16 (BAT) of the DLC3.

Detection Item Trouble Area
No resistance exists between terminal 6 (CA3H) of the central gateway ECU and terminal 16 (BAT) of the DLC3, or terminal 21 (CA3L) of the central gateway ECU and terminal 16 (BAT) of the DLC3.

  • Short to +B in bus 3 CAN main wires

  • Short to +B in bus 3 CAN branch wires

  • Central gateway ECU

  • Multi-media module receiver assembly*1

  • Bus buffer ECU*2

  • Option connector*3

  • No. 5 CAN junction connector

  • No. 6 CAN junction connector

  • No. 2 CAN junction terminal

WIRING DIAGRAM

A01WYWDE01

CAUTION / NOTICE / HINT

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, 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 battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

  • 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 ignition switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

  • 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 B+ IN CAN BUS WIRE (CENTRAL GATEWAY ECU - NO. 5 CAN JUNCTION CONNECTOR)


    1. A01X7LEE01
      Text in Illustration
      *a

      Front view of wire harness connector

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

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

    2. Disconnect the central gateway ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E145-6 (CA3H) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E145-21 (CA3L) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

    OK

    REPLACE CENTRAL GATEWAY ECU Click here

    NG

  2. CONNECT CONNECTOR


    1. Reconnect the E145 central gateway ECU connector.


    NEXT

  3. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 2 CAN JUNCTION TERMINAL - NO. 6 CAN JUNCTION CONNECTOR)


    1. A01X6ZAE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 CAN Junction Terminal)
      *b Front view of DLC3

      Disconnect the No. 2 CAN junction terminal connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F98-3 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      F98-2 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

    OK

    REPLACE NO. 2 CAN JUNCTION TERMINAL

    NG

  4. CONNECT CONNECTOR


    1. Reconnect the F98 No. 2 CAN junction terminal connector.


    NEXT

  5. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 5 CAN JUNCTION CONNECTOR)

    Tech Tips

    If there is a short to B+ in the connection line while accessory parts are not connected, repair or replace the CAN bus branch line or connector.


    1. Disconnect the No. 5 CAN junction connector.

      A01X9SNE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 5 CAN Junction Connector)

      		 *b Front view of DLC3
      *c to Central Gateway ECU *d to Bus Buffer ECU (w/ Bus Buffer ECU)
      *e

      • to Multi-media Module Receiver Assembly (for Multi-media Module Receiver Type)

      • to Option Connector (w/ Option Connector)

      		 *f to No. 6 CAN Junction Connector

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connect to
      E152-8 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Central gateway ECU
      E152-19 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E152-9 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Bus buffer ECU*1
      E152-20 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E152-10 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      • Multi-media module receiver assembly*2

      • Option connector*3
      E152-21 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E152-11 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher No. 6 CAN junction connector
      E152-22 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      • *1: w/ Bus Buffer ECU

      • *2: for Multi-media Module Receiver Type

      • *3: w/ Option Connector

      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU CAN main wire) B
      NG (No. 6 CAN junction connector CAN main wire) C
      NG (ECU or sensor CAN branch wires) D

    A

    REPLACE NO. 5 CAN JUNCTION CONNECTOR

    B

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

    D

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

    C

  6. CONNECT CONNECTOR


    1. Reconnect the E152 No. 5 CAN junction connector.


    NEXT

  7. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (NO. 6 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 6 CAN junction connector.

      A01X0DIE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 6 CAN Junction Connector)

      		 *b Front view of DLC3
      *c to No. 5 CAN Junction Connector *d to No. 2 CAN Junction Terminal

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connect to
      F99-6 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher No. 5 CAN junction connector
      F99-17 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      F99-7 (CANH) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher No. 2 CAN junction terminal
      F99-18 (CANL) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      Result
      Result Proceed to
      OK A
      NG (No. 5 CAN junction connector CAN main wire) B
      NG (No. 2 CAN junction terminal CAN main wire) C

    A

    REPLACE NO. 6 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - NO. 5 CAN JUNCTION CONNECTOR)

    C

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 6 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION TERMINAL)

  8. CHECK FOR SHORT TO B+ IN CAN BUS WIRE (ECU, SENSOR)


    1. A01X7J4E02
      Text in Illustration
      *a

      Component with harness connected

      (Central Gateway ECU)
      *b Front view of DLC3

      Reconnect the CAN junction connector.

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E145-6 (CA3H) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      E145-21 (CA3L) - E22-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher

      Tech Tips

      If the resistance changes to 6 kΩ or higher when the connector is disconnected from the ECU or sensor, there may be a short in the ECU or sensor.


    OK

    REPLACE CORRESPONDING ECU OR SENSOR

    NG

    REPAIR OR REPLACE CORRESPONDING ECU OR SENSOR CAN BRANCH WIRES OR CONNECTOR