CAN COMMUNICATION SYSTEM(w/ Central Gateway ECU) Check Bus 2 Line for Short to +B (RHD Models)

DESCRIPTION

There may be a short circuit between one of the CAN bus lines and +B when no resistance exists between terminal 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 17 (CA4L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3.

Symptom Trouble Area
No resistance exists between terminal 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3, or terminal 17 (CA4L) of the central gateway ECU (network gateway ECU) and terminal 16 (BAT) of the DLC3.

  • Short to +B in CAN main bus line

  • Short to +B in CAN branch line

    Central gateway ECU (network gateway ECU)

  • Hybrid vehicle control ECU

  • ECM

  • Main body ECU (multiplex network body ECU)

  • Combination meter sub-assembly

  • Brake booster with master cylinder assembly (skid control ECU)

  • Spiral cable with sensor sub-assembly (steering angle sensor)

  • Air conditioning amplifier assembly

  • Power steering ECU assembly

  • Airbag ECU assembly

  • Transmission control ECU assembly

  • Certification ECU (smart key ECU assembly)

  • No. 1 CAN junction connector

  • No. 2 CAN junction connector

  • No. 3 CAN junction connector

WIRING DIAGRAM

B005Z9FE02
B005YJFE02

CAUTION / NOTICE / HINT

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), turn the cruise control system on using the cruise control switch (ON/OFF switch), wait at least 60 seconds, and then drive the vehicle at a speed of 50 km/h (31 mph) or more for at least 1.72 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


  • 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 +B IN CAN BUS LINE (NO. 2 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the L94 wire harness connector from the No. 2 CAN junction connector (instrument panel connector holder left side).

    3. B005YJYE03
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 2 CAN Junction Connector)
      *b to No. 1 CAN Junction Connector
      *c to No. 3 CAN Junction Connector
      *d to Certification ECU (Smart Key ECU Assembly)
      *e to Spiral Cable with Sensor Sub-assembly (Steering Angle Sensor)

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L94-1 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher No. 1 CAN junction connector
      L94-2 (CANL) - L61-16 (BAT)
      L94-4 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher No. 3 CAN junction connector
      L94-5 (CANL) - L61-16 (BAT)
      L94-7 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Certification ECU (smart key ECU assembly)
      L94-8 (CANL) - L61-16 (BAT)
      L94-10 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Spiral cable with sensor sub-assembly (steering angle sensor)
      L94-11 (CANL) - L61-16 (BAT)
      Result
      Result Proceed to
      OK A
      NG (Line to No. 1 CAN junction connector) B
      NG (Line to No. 3 CAN junction connector) C
      NG (Line to ECU or sensor) D

    B

    CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 CAN JUNCTION CONNECTOR) Click here

    C

    CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 3 CAN JUNCTION CONNECTOR) Click here

    D

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

    A

  2. CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 2 CAN JUNCTION CONNECTOR)


    1. Disconnect the L95 wire harness connector from the No. 2 CAN junction connector (instrument panel connector holder right side).

    2. B005YVBE02
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 2 CAN Junction Connector)
      *b to Power Steering ECU Assembly
      *c to Air Conditioning Amplifier Assembly
      *d to Airbag ECU Assembly
      *e to Central Gateway ECU (Network Gateway ECU)

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      L95-3 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Power steering ECU assembly
      L95-2 (CANL) - L61-16 (BAT)
      L95-6 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Air conditioning amplifier assembly
      L95-5 (CANL) - L61-16 (BAT)
      L95-9 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Airbag ECU assembly
      L95-8 (CANL) - L61-16 (BAT)
      L95-12 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Central gateway ECU (network gateway ECU)
      L95-11 (CANL) - L61-16 (BAT)

    OK

    REPLACE NO. 2 CAN JUNCTION CONNECTOR

    NG

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

  3. CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 CAN JUNCTION CONNECTOR)


    1. B005Y98E03

      Disconnect the L132 wire harness connector from the No. 1 CAN junction connector (instrument panel wire side).

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

      Standard Resistance
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)
      *b to No. 2 CAN Junction Connector
      *c to Combination Meter Sub-assembly
      Tester Connection Condition Specified Condition Connected to
      L132-5 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher No. 2 CAN junction connector
      L132-11 (CANL) - L61-16 (BAT)
      L132-6 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Combination meter sub-assembly
      L132-12 (CANL) - L61-16 (BAT)
      Result
      Result Proceed to
      OK A
      NG (Line to No. 2 CAN junction connector) B
      NG (Line to combination meter sub-assembly) C

    B

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR - NO. 2 CAN JUNCTION CONNECTOR)

    C

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

    A

  4. CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 1 CAN JUNCTION CONNECTOR)


    1. B005YPWE02

      Disconnect the A67 wire harness connector from the No. 1 CAN junction connector (engine room main wire side).

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

      Standard Resistance
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)
      *b to Brake Booster with Master Cylinder Assembly (Skid Control ECU)
      Tester Connection Condition Specified Condition
      A67-1 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      A67-7 (CANL) - L61-16 (BAT)

    OK

    REPLACE NO. 1 CAN JUNCTION CONNECTOR

    NG

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

  5. CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 3 CAN JUNCTION CONNECTOR)


    1. B005YP0E02

      Disconnect the L133 wire harness connector from the No. 3 CAN junction connector (instrument panel wire side).

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

      Standard Resistance
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)
      *b to Hybrid Vehicle Control ECU
      *c to Main Body ECU (Multiplex Network Body ECU)
      *d to No. 2 CAN Junction Connector
      Tester Connection Condition Specified Condition Connected to
      L133-4 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Hybrid vehicle control ECU
      L133-10 (CANL) - L61-16 (BAT)
      L133-5 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Main body ECU (multiplex network body ECU)
      L133-11 (CANL) - L61-16 (BAT)
      L133-6 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher No. 2 CAN junction connector
      L133-12 (CANL) - L61-16 (BAT)
      Result
      Result Proceed to
      OK A
      NG (Line to No. 2 CAN junction connector) B
      NG (Line to ECU or sensor) C

    B

    REPAIR OR REPLACE CAN MAIN BUS LINE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 3 CAN JUNCTION CONNECTOR)

    C

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

    A

  6. CHECK FOR SHORT TO +B IN CAN BUS LINE (NO. 3 CAN JUNCTION CONNECTOR)


    1. B005YMJE02
      Text in Illustration
      *1 DLC3
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)
      *b to ECM
      *c to Transmission Control ECU Assembly

      Disconnect the A68 wire harness connector from the No. 3 CAN junction connector (engine room main wire side).

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A68-1 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher ECM
      A68-7 (CANL) - L61-16 (BAT)
      A68-2 (CANH) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher Transmission control ECU assembly
      A68-8 (CANL) - L61-16 (BAT)

    OK

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    NG

  7. CHECK FOR SHORT TO +B IN CAN BUS LINE (ECU OR SENSOR)


    1. Reconnect all wire harness connectors.

    2. Disconnect the ECU or sensor connected to the CAN bus line that is shorted to +B.

      Tech Tips

      If the ECU or sensor has multiple connectors, disconnect the connector that includes the CAN bus lines. To determine the ECU or sensor that is connected to the shorted bus line, refer to the terminals of ECU tables Click here.

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

      B005Z14E03
      Text in Illustration
      *1 DLC3 - -
      *a

      Component with harness connected

      (Central Gateway ECU (Network Gateway ECU))

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      L192-18 (CA4H) - L61-16 (BAT) Cable disconnected from negative (-) auxiliary battery terminal 6 kΩ or higher
      L192-17 (CA4L) - L61-16 (BAT)

      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 ECU OR SENSOR

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR