CAN COMMUNICATION SYSTEM(w/ 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.

Symptom 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 main lines

  • Short to +B in bus 3 branch lines

  • Telematics transceiver*

  • Radio receiver assembly

  • No. 3 CAN junction connector

*: w/ Telematics Transceiver

WIRING DIAGRAM

A01W15PE07

CAUTION / NOTICE / HINT

Note


  • 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.

  • 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 engine switch on (IG) and wait at least 31 seconds.

  • After the repair, perform the 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 engine 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 SHORT TO +B IN CAN BUS LINE (NO. 3 CAN J/C)


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

    2. Disconnect the H199 No. 3 CAN junction connector.

      A01W3P7E02
      Text in Illustration
      *1 DLC3 - -
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)

      		 *b to Central Gateway ECU
      *c to Central Gateway ECU *d to Radio Receiver Assembly
      *e

      to Telematics Transceiver

      (w/ Telematics Transceiver)

      		 - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      H199-1 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Central gateway ECU
      H199-12 (CANL) - H29-16 (BAT)
      H199-2 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Central gateway ECU
      H199-13 (CANL) - H29-16 (BAT)
      H199-3 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Radio receiver assembly
      H199-14 (CANL) - H29-16 (BAT)
      H199-4 (CANH) - H29-16 (BAT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher Telematics transceiver*
      H199-15 (CANL) - H29-16 (BAT)

      *: w/ Telematics Transceiver

      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU main line) B
      NG (ECU or sensor branch line) C

    A

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    C

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

    B

  2. CHECK FOR SHORT TO +B IN CAN BUS LINE (CENTRAL GATEWAY ECU)


    1. A01W0R8E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Central Gateway ECU)

      Disconnect the H193 central gateway ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H193-6 (CA3H) - H193-1 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      H193-21 (CA3L) - H193-1 (BATT)
      H193-19 (CAYH) - H193-1 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      H193-20 (CAYL) - H193-1 (BATT)

    OK

    REPLACE CENTRAL GATEWAY ECU Click here

    NG

    REPAIR OR REPLACE CAN MAIN BUS LINE (CENTRAL GATEWAY ECU - NO. 3 CAN J/C)

  3. CHECK FOR SHORT TO +B IN CAN BUS LINE (ECU, SENSOR)


    1. Reconnect the H199 No. 3 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 Click here.

    3. A01VZL3E02
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Central Gateway ECU)

      Disconnect the H193 central gateway ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      H193-6 (CA3H) - H193-1 (BATT) Cable disconnected from negative (-) battery terminal 6 kΩ or higher
      H193-21 (CA3L) - H193-1 (BATT)

      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 BUS LINE OR CONNECTOR