CAN COMMUNICATION SYSTEM(w/ Central Gateway ECU) Check Bus 2 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 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 17 (CA4L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Symptom Trouble Area
There is no resistance between terminal 18 (CA4H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 17 (CA4L) 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 bus line

  • Central gateway ECU (network gateway ECU)

  • ECM

  • Air conditioning amplifier assembly

  • 4 wheel drive control ECU (4WD control ECU)

  • Certification ECU (smart key ECU assembly)*1

  • Power steering ECU assembly

  • Master cylinder solenoid (skid control ECU)*2

  • Brake actuator assembly (skid control ECU)*3

  • Airbag sensor assembly

  • Spiral cable with steering angle sensor

  • Combination meter assembly

  • Tire pressure warning ECU and receiver*4

  • Main body ECU (multiplex network body ECU)

  • No. 1 headlight ECU sub-assembly LH*5

  • No. 2 CAN junction connector

  • No. 6 CAN junction connector
*1: w/ Entry and Start System
*2: except 2TR-FE
*3: for 2TR-FE
*4: w/ Tire Pressure Warning System
*5: for LED Headlight

WIRING DIAGRAM

B001F7VE01
B001CDWE01

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

  • When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

  • Before replacing the certification ECU (smart key ECU assembly), refer to Service Bulletin.

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. 6 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the No. 6 CAN junction connector.

      B001EHXC03
      *a

      Front view of wire harness connector

      (to No. 6 CAN Junction Connector)

      		 *b Front view of DLC3
      *c to No. 2 CAN Junction Connector *d to 4 Wheel Drive Control ECU (4WD Control ECU)
      *e to Certification ECU (Smart Key ECU Assembly) (w/ Entry and Start System) *f to No. 1 Headlight ECU Sub-assembly LH (for RHD with LED Headlight)
      *g to Tire Pressure Warning ECU and Receiver (for RHD with Tire Pressure Warning System) *h to Central Gateway ECU (Network Gateway ECU)
      *i to Air Conditioning Amplifier Assembly *j to Power Steering ECU Assembly
      *k to Brake Actuator Assembly (Skid Control ECU) (for 2TR-FE) *l to ECM

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G290-1 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 2 CAN junction connector
      G290-11 (CANL) - G48-4 (CG)
      G290-2 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher 4 Wheel drive control ECU (4WD control ECU)
      G290-12 (CANL) - G48-4 (CG)
      G290-3 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Certification ECU (smart key ECU assembly)*1
      G290-13 (CANL) - G48-4 (CG)
      G290-4 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 1 headlight ECU sub-assembly LH*2
      G290-14 (CANL) - G48-4 (CG)
      G290-5 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Tire pressure warning ECU and receiver*3
      G290-15 (CANL) - G48-4 (CG)
      G290-6 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Central gateway ECU (network gateway ECU)
      G290-16 (CANL) - G48-4 (CG)
      G290-7 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Air conditioning amplifier assembly
      G290-17 (CANL) - G48-4 (CG)
      G290-8 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Power steering ECU assembly
      G290-18 (CANL) - G48-4 (CG)
      G290-9 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Brake actuator assembly (skid control ECU)*4
      G290-19 (CANL) - G48-4 (CG)
      G290-10 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher ECM
      G290-20 (CANL) - G48-4 (CG)
      *1: w/ Entry and Start System
      *2: for RHD with LED Headlight
      *3: for RHD with Tire Pressure Warning System
      *4: for 2TR-FE
      Result
      Result Proceed to
      OK A
      NG (No. 2 CAN junction connector CAN main wire) B
      NG (Central gateway ECU [network gateway ECU] CAN branch wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 6 CAN JUNCTION CONNECTOR

    C

    CONNECT CONNECTOR Click here

    D

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

    B

  2. CONNECT CONNECTOR


    1. Reconnect the G290 No. 6 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 2 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 2 CAN junction connector.

      B001EHXC04
      *a

      Front view of wire harness connector

      (to No. 2 CAN Junction Connector)

      		 *b Front view of DLC3
      *c to No. 6 CAN Junction Connector *d to Spiral Cable with Steering Angle Sensor
      *e to Airbag Sensor Assembly *f to No. 1 Headlight ECU Sub-assembly LH (for LHD with LED Headlight)
      *g to Tire Pressure Warning ECU and Receiver (for LHD with Tire Pressure Warning System) *h to Combination Meter Assembly
      *i to Main Body ECU (Multiplex Network Body ECU) *j to Master Cylinder Solenoid (Skid Control ECU) (except 2TR-FE)

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G286-1 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 6 CAN junction connector
      G286-11 (CANL) - G48-4 (CG)
      G286-2 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Spiral cable with steering angle sensor
      G286-12 (CANL) - G48-4 (CG)
      G286-3 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Airbag sensor assembly
      G286-13 (CANL) - G48-4 (CG)
      G286-4 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 1 headlight ECU sub-assembly LH*1
      G286-14 (CANL) - G48-4 (CG)
      G286-7 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Tire pressure warning ECU and receiver*2
      G286-17 (CANL) - G48-4 (CG)
      G286-8 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Combination meter assembly
      G286-18 (CANL) - G48-4 (CG)
      G286-9 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Main body ECU (multiplex network body ECU)
      G286-19 (CANL) - G48-4 (CG)
      G286-10 (CANH) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Master cylinder solenoid (skid control ECU)*3
      G286-20 (CANL) - G48-4 (CG)
      *1: for LHD with LED Headlight
      *2: for LHD with Tire Pressure Warning System
      *3: except 2TR-FE
      Result
      Result Proceed to
      OK A
      NG (No. 6 CAN junction connector CAN main wire) B
      NG (Wire to ECU or sensor) C

    A

    REPLACE NO. 2 CAN JUNCTION CONNECTOR

    B

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

    C

    GO TO STEP 6 Click here

  4. CONNECT CONNECTOR


    1. Reconnect the G290 No. 6 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 6 CAN JUNCTION CONNECTOR)


    1. B001HSMC99
      *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
      G229-18 (CA4H) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G229-17 (CA4L) - G48-4 (CG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN BUS BRANCH WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 6 CAN JUNCTION CONNECTOR)

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


    1. Reconnect the 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. B001HWOC35
      *a

      Component with harness connected

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G229-18 (CA4H) - G48-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G229-17 (CA4L) - 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