CAN COMMUNICATION SYSTEM Check Bus 5 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 15 (CA5H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

Symptom Trouble Area
There is no resistance between terminal 15 (CA5H) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3, or terminal 16 (CA5L) of the central gateway ECU (network gateway ECU) and terminal 4 (CG) of the DLC3.

  • Short to GND in CAN main bus wire

  • Short to GND in CAN branch wire

  • Central gateway ECU (network gateway ECU)

  • Certification ECU (smart key ECU assembly)

  • Meter mirror Sub-assembly*1

  • Multiplex tilt and telescopic ECU

  • Main body ECU (multiplex network body ECU)

  • Air conditioning amplifier assembly

  • Headlight ECU sub-assembly LH

  • Front multiplex network door ECU LH

  • Position control ECU assembly

  • Front multiplex network door ECU RH

  • Rear power seat switch (rear multi operation panel)*2

  • No. 2 position control ECU assembly

  • Headlight ECU sub-assembly RH

  • Combination meter assembly

  • No. 2 CAN junction connector

  • No. 10 CAN junction connector

  • No. 11 CAN junction connector
*1: w/ Headup Display System
*2: w/ Rear Multi Operation Panel System

WIRING DIAGRAM


  1. for LHD:

    B0069SEE01
    B006AFGE01

  2. for RHD:

    B0069SEE02
    B006AFGE02

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 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

  • 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 engine switch on (IG) 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.

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. 11 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the L116 No. 11 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
      L116-1 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 2 CAN junction connector
      L116-7 (CANL) - G20-4 (CG)
      L116-2 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Front multiplex network door ECU LH
      L116-8 (CANL) - G20-4 (CG)
      L116-3 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 10 CAN junction connector
      L116-9 (CANL) - G20-4 (CG)
      L116-4 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Position control ECU assembly*1

      • No. 2 position control ECU assembly*2
      L116-10 (CANL) - G20-4 (CG)
      L116-5 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Rear power seat switch (rear multi operation panel)*3
      L116-11 (CANL) - G20-4 (CG)
      *1: for LHD
      *2: for RHD
      *3: w/ Rear Multi Operation Panel System
      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU [network gateway ECU] CAN main wire) B
      NG (No. 10 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 11 CAN JUNCTION CONNECTOR

    C

    CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 10 CAN JUNCTION CONNECTOR) Click here

    D

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

    B

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


    1. Reconnect the L116 No. 11 CAN junction connector.

    2. Disconnect the G120 No. 2 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
      G120-11 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Central gateway EUC (network gateway ECU)*1

      • Combination meter assembly*2
      G120-1 (CANL) - G20-4 (CG)
      G120-12 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Meter mirror Sub-assembly*3

      • Certification ECU (smart key ECU assembly)*2
      G120-2 (CANL) - G20-4 (CG)
      G120-13 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Certification ECU (smart key ECU assembly)*1

      • Meter mirror Sub-assembly*4
      G120-3 (CANL) - G20-4 (CG)
      G120-14 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Air conditioning amplifier assembly*1

      • Multiplex tilt and telescopic ECU*2
      G120-4 (CANL) - G20-4 (CG)
      G120-15 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Main body ECU (multiplex network body ECU)
      G120-5 (CANL) - G20-4 (CG)
      G120-16 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Multiplex tilt and telescopic ECU*1

      • Air conditioning amplifier assembly*2
      G120-6 (CANL) - G20-4 (CG)
      G120-17 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 11 CAN junction connector
      G120-7 (CANL) - G20-4 (CG)
      *1: for LHD
      *2: for RHD
      *3: for LHD with Headup Display System
      *4: for RHD with Headup Display System
      Result
      Result Proceed to
      OK A
      NG (Central gateway EUC [network gateway ECU] CAN main wire) B
      NG (No. 11 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 2 CAN JUNCTION CONNECTOR

    C

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 2 CAN JUNCTION CONNECTOR - NO. 11 CAN JUNCTION CONNECTOR)

    D

    GO TO STEP 6 Click here

    B

  3. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 2 CAN JUNCTION CONNECTOR)


    1. Reconnect the G120 No. 2 CAN junction connector.

    2. Disconnect the G66 central gateway ECU (network gateway ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G66-15 (CA5H) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G66-16 (CA5L) - G20-4 (CG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 2 CAN JUNCTION CONNECTOR)

  4. CHECK FOR SHORT TO GND IN CAN BUS WIRE (NO. 10 CAN JUNCTION CONNECTOR)


    1. Reconnect the L116 No. 11 CAN junction connector.

    2. Disconnect the L115 No. 10 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
      L115-1 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Front multiplex network door ECU RH
      L115-7 (CANL) - G20-4 (CG)
      L115-2 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • No. 2 position control ECU assembly*1

      • Position control ECU assembly*2
      L115-8 (CANL) - G20-4 (CG)
      L115-3 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher

      • Central gateway EUC (network gateway ECU)*1

      • Combination meter assembly*2
      L115-9 (CANL) - G20-4 (CG)
      L115-4 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher No. 11 CAN junction connector
      L115-10 (CANL) - G20-4 (CG)
      L115-5 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Headlight ECU sub-assembly LH
      L115-11 (CANL) - G20-4 (CG)
      L115-6 (CANH) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher Headlight ECU sub-assembly RH
      L115-12 (CANL) - G20-4 (CG)
      *1: for LHD
      *2: for RHD
      Result
      Result Proceed to
      OK A
      NG (No. 11 CAN junction connector CAN main wire) B
      NG (Central gateway ECU [network gateway ECU] CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 10 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (NO. 10 CAN JUNCTION CONNECTOR - NO. 11 CAN JUNCTION CONNECTOR)

    D

    GO TO STEP 6 Click here

    C

  5. CHECK FOR SHORT TO GND IN CAN BUS WIRE (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 10 CAN JUNCTION CONNECTOR)


    1. Reconnect the L115 No. 10 CAN junction connector.

    2. Disconnect the G66 central gateway ECU (network gateway ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G66-15 (CA5H) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G66-16 (CA5L) - G20-4 (CG)
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN MAIN WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 10 CAN JUNCTION CONNECTOR)

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


    1. Reconnect all wire harness connectors.

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

      Click here

    3. B006FRUC22
      *a

      Component with harness connected

      (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
      G66-15 (CA5H) - G20-4 (CG) Cable disconnected from negative (-) battery terminal 200 Ω or higher
      G66-16 (CA5L) - G20-4 (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 ground 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

    REPAIR OR REPLACE HARNESS OR CONNECTOR