CAN COMMUNICATION SYSTEM(w/ Central Gateway ECU) Check Bus 5 Lines for Short Circuit

DESCRIPTION

There may be a short circuit between the CAN main bus lines and/or CAN branch lines when the resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU (network gateway ECU) is below 54 Ω.

Symptom Trouble Area
Resistance between terminals 15 (CA5H) and 16 (CA5L) of the central gateway ECU (network gateway ECU) is below 54 Ω.

  • Short in CAN main bus lines

  • Short in CAN branch lines

  • Central gateway ECU (network gateway ECU)

  • Parking assist ECU*1

  • Driving support ECU assembly*2

  • Clearance warning ECU assembly*3

  • Stabilizer control ECU*4

  • Forward recognition camera*5

  • Blind spot monitor sensor LH*6

  • Millimeter wave radar sensor assembly*2

  • Suspension control ECU*7

  • No. 1 CAN junction terminal

  • No. 1 CAN junction connector

  • No. 3 CAN Junction connector

  • No. 7 CAN Junction connector
*1: w/ Parking Assist Monitor System
*2: w/ Pre-crash Safety System
*3: w/ TOYOTA Parking Assist-sensor System (w/ Multi-display)
*4: w/ Kinetic Dynamic Suspension System
*5: w/ Pre-crash Safety System
*6: w/ Blind Spot Monitor System
*7: w/ Air Suspension System

WIRING DIAGRAM


  1. for LHD:

    B001GXJE01
    B001HAZE01

  2. for RHD:

    B001D06E01
    B001D9TE01

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

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 VEHICLE TYPE


    1. Check vehicle type.

      Result
      Result Proceed to
      for LHD A
      for RHD B

    B

    CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 CAN JUNCTION CONNECTOR) Click here

    A

  2. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the No. 3 CAN junction connector.

      B001DAJC47
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)

      		 *b to No. 7 CAN Junction Connector
      *c to Stabilizer Control ECU (w/ Kinetic Dynamic Suspension System) *d to Forward Recognition Camera (w/ Pre-crash Safety System)
      *e to Blind Spot Monitor Sensor LH (w/ Blind Spot Monitor System) *f to No. 1 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
      G287-1 (CANH) - G287-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 7 CAN junction connector
      G287-2 (CANH) - G287-12 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Stabilizer control ECU*1
      G287-3 (CANH) - G287-13 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Forward recognition camera*2
      G287-9 (CANH) - G287-19 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Blind spot monitor sensor LH*3
      G287-10 (CANH) - G287-20 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction connector
      *1: w/ Kinetic Dynamic Suspension System
      *2: w/ Pre-crash Safety System
      *3: w/ Blind Spot Monitor System
      Result
      Result Proceed to
      OK A
      NG (No. 1 CAN junction connector CAN main wire) B
      NG (No. 7 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    C

    CONNECT CONNECTOR Click here

    D

    GO TO STEP 20 Click here

    B

  3. CONNECT CONNECTOR


    1. Reconnect the G287 No. 3 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  4. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION CONNECTOR)


    1. B001E85C01
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)
      *b to Suspension Control ECU (w/ Air Suspension System)
      *c to Millimeter Wave Radar Sensor Assembly (w/ Pre-crash Safety System)
      *d to No. 1 CAN Junction Terminal
      *e to No. 3 CAN Junction Connector

      Disconnect the No. 1 CAN junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A121-1 (CANH) - A121-7 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Suspension control ECU*1
      A121-2 (CANH) - A121-8 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Millimeter wave radar sensor assembly*2
      A121-4 (CANH) - A121-10 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction terminal
      A121-5 (CANH) - A121-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 3 CAN junction connector
      *1: w/ Air Suspension System
      *2: w/ Pre-crash Safety System
      Result
      Result Proceed to
      OK A
      NG (No. 1 CAN junction terminal CAN main wire) B
      NG (No. 3 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 1 CAN JUNCTION CONNECTOR

    C

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR- NO. 3 CAN JUNCTION CONNECTOR)

    D

    GO TO STEP 20 Click here

    B

  5. CONNECT CONNECTOR


    1. Reconnect the A121 No. 1 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  6. CHECK SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION TERMINAL - NO. 1 CAN JUNCTION CONNECTOR)


    1. B001CRBC77
      *a

      Rear view of wire harness connector

      (to No. 1 CAN Junction Terminal)

      Disconnect the No. 1 CAN junction terminal connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G298-3 (CANH) - G298-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 1 CAN JUNCTION TERMINAL

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 1 CAN JUNCTION TERMINAL - NO. 1 CAN JUNCTION CONNECTOR)

  7. CONNECT CONNECTOR


    1. Reconnect the G287 No. 3 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  8. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 7 CAN junction connector.

      B001DAJC48
      *a

      Front view of wire harness connector

      (to No. 7 CAN Junction Connector)

      		 *b to No. 3 CAN Junction Connector
      *c to Central Gateway ECU (Network Gateway ECU) *d to Parking Assist ECU (w/ Parking Assist Monitor System)
      *e to Driving Support ECU Assembly (w/ Pre-crash Safety System) *f to Clearance Warning ECU Assembly (w/ TOYOTA Parking Assist-sensor System [w/ Multi-display])

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G291-1 (CANH) - G291-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 3 CAN junction connector
      G291-2 (CANH) - G291-12 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)
      G291-3 (CANH) - G291-13 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Parking assist ECU*1
      G291-4 (CANH) - G291-14 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving support ECU assembly*2
      G291-5 (CANH) - G291-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Clearance warning ECU assembly*3
      *1: w/ Parking Assist Monitor System
      *2: w/ Pre-crash Safety System
      *3: w/ TOYOTA Parking Assist-sensor System (w/ Multi-display)
      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU [network gateway ECU] CAN main wire) B
      NG (No. 3 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 7 CAN JUNCTION CONNECTOR

    C

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 7 CAN JUNCTION CONNECTOR- NO. 3 CAN JUNCTION CONNECTOR)

    D

    GO TO STEP 20 Click here

    B

  9. CONNECT CONNECTOR


    1. Reconnect the G291 No. 7 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  10. CHECK FOR SHORT IN CAN BUS WIRES (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 7 CAN JUNCTION CONNECTOR)


    1. B001GIOC22
      *a

      Front view of wire harness connector

      (to Central Gateway ECU [Network Gateway ECU])

      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
      G229-15 (CA5H) - G229-16 (CA5L) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 7 CAN JUNCTION CONNECTOR)

  11. CHECK FOR SHORT IN CAN BUS WIRES (NO. 7 CAN JUNCTION CONNECTOR)


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

    2. Disconnect the No. 7 CAN junction connector.

      B001DAJC49
      *a

      Front view of wire harness connector

      (to No. 7 CAN Junction Connector)

      		 *b to No. 3 CAN Junction Connector
      *c to No. 1 CAN Junction Connector *d to Driving Support ECU Assembly (w/ Pre-crash Safety System)
      *e to Forward Recognition Camera (w/ Pre-crash Safety System) *f to Blind Spot Monitor Sensor LH (w/ Blind Spot Monitor System)
      *g to Clearance Warning ECU Assembly (w/ TOYOTA Parking Assist-sensor System [for 8 Sensor Type with Multi-display]) - -

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G291-1 (CANH) - G291-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 3 CAN junction connector
      G291-3 (CANH) - G291-13 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction connector
      G291-4 (CANH) - G291-14 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Driving support ECU assembly*1
      G291-5 (CANH) - G291-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Forward recognition camera*1
      G291-6 (CANH) - G291-16 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Blind spot monitor sensor LH*2
      G291-7 (CANH) - G291-17 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Clearance warning ECU assembly*3
      *1: w/ Pre-crash Safety System
      *2: w/ Blind Spot Monitor System
      *3: w/ TOYOTA Parking Assist-sensor System (for 8 Sensor Type with Multi-display)
      Result
      Result Proceed to
      OK A
      NG (No. 1 CAN junction connector CAN main wire) B
      NG (No. 3 CAN junction connector CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 7 CAN JUNCTION CONNECTOR

    C

    CONNECT CONNECTOR Click here

    D

    GO TO STEP 20 Click here

    B

  12. CONNECT CONNECTOR


    1. Reconnect the G291 No. 7 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION CONNECTOR)


    1. B001E85C02
      *a

      Front view of wire harness connector

      (to No. 1 CAN Junction Connector)
      *b to Suspension Control ECU (w/ Air Suspension System)
      *c to Millimeter Wave Radar Sensor Assembly (w/ Pre-crash Safety System)
      *d to No. 7 CAN Junction Connector
      *e to Central Gateway ECU (Network Gateway ECU)

      Disconnect the No. 1 CAN junction connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      A121-1 (CANH) - A121-7 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Suspension control ECU*1
      A121-2 (CANH) - A121-8 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Millimeter wave radar sensor assembly*2
      A121-4 (CANH) - A121-10 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 7 CAN junction connector
      A121-5 (CANH) - A121-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω Central gateway ECU (network gateway ECU)
      *1: w/ Air Suspension System
      *2: w/ Pre-crash Safety System
      Result
      Result Proceed to
      OK A
      NG (Central gateway ECU [network gateway ECU] CAN main wire) B
      NG (No. 7 CAN junction terminal CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 1 CAN JUNCTION CONNECTOR

    C

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 1 CAN JUNCTION CONNECTOR- NO. 7 CAN JUNCTION CONNECTOR)

    D

    GO TO STEP 20 Click here

    B

  14. CONNECT CONNECTOR


    1. Reconnect the A121 No. 1 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  15. CHECK FOR SHORT IN CAN BUS WIRES (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 1 CAN JUNCTION CONNECTOR)


    1. B001GIOC22
      *a

      Front view of wire harness connector

      (to Central Gateway ECU [Network Gateway ECU])

      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
      G229-15 (CA5H) - G229-16 (CA5L) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE CENTRAL GATEWAY ECU (NETWORK GATEWAY ECU) Click here

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (CENTRAL GATEWAY ECU [NETWORK GATEWAY ECU] - NO. 1 CAN JUNCTION CONNECTOR)

  16. CONNECT CONNECTOR


    1. Reconnect the G291 No. 7 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  17. CHECK FOR SHORT IN CAN BUS WIRES (NO. 3 CAN JUNCTION CONNECTOR)


    1. Disconnect the No. 3 CAN junction connector.

      B001DAJC50
      *a

      Front view of wire harness connector

      (to No. 3 CAN Junction Connector)

      		 *b to No. 7 CAN Junction Connector
      *c to Stabilizer Control ECU (w/ Kinetic Dynamic Suspension System) *d to Parking Assist ECU (w/ Parking Assist Monitor System)
      *e to Clearance Warning ECU Assembly (w/ TOYOTA Parking Assist-sensor System [for 4 Sensor Type with Multi-display]) *f to No. 1 CAN Junction Terminal

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

      Standard Resistance
      Tester Connection Condition Specified Condition Connected to
      G287-1 (CANH) - G287-11 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 7 CAN junction connector
      G287-2 (CANH) - G287-12 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Stabilizer control ECU*1
      G287-4 (CANH) - G287-14 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Parking assist ECU*2
      G287-5 (CANH) - G287-15 (CANL) Cable disconnected from negative (-) battery terminal 200 Ω or higher Clearance warning ECU assembly*3
      G287-10 (CANH) - G287-20 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω No. 1 CAN junction terminal
      *1: w/ Kinetic Dynamic Suspension System
      *2: w/ Parking Assist Monitor System
      *3: w/ TOYOTA Parking Assist-sensor System (for 4 Sensor Type with Multi-display)
      Result
      Result Proceed to
      OK A
      NG (No. 7 CAN junction connector CAN main wire) B
      NG (No. 1 CAN junction terminal CAN main wire) C
      NG (Wire to ECU or sensor) D

    A

    REPLACE NO. 3 CAN JUNCTION CONNECTOR

    B

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 3 CAN JUNCTION CONNECTOR- NO. 7 CAN JUNCTION CONNECTOR)

    D

    CHECK FOR SHORT IN CAN BUS WIRES (ECU, SENSOR) Click here

    C

  18. CONNECT CONNECTOR


    1. Reconnect the G287 No. 3 CAN junction connector.

      Result
      Proceed to
      NEXT

    NEXT

  19. CHECK SHORT IN CAN BUS WIRES (NO. 1 CAN JUNCTION TERMINAL - NO. 3 CAN JUNCTION CONNECTOR)


    1. B001CRBC77
      *a

      Rear view of wire harness connector

      (to No. 1 CAN Junction Terminal)

      Disconnect the No. 1 CAN junction terminal connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G298-3 (CANH) - G298-2 (CANL) Cable disconnected from negative (-) battery terminal 108 to 132 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE NO. 1 CAN JUNCTION TERMINAL

    NG

    REPAIR OR REPLACE CAN BUS MAIN WIRE OR CONNECTOR (NO. 1 CAN JUNCTION TERMINAL - NO. 3 CAN JUNCTION CONNECTOR)

  20. CHECK FOR SHORT IN CAN BUS WIRES (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 short circuited branch line is connected.

      Click here

    3. B001CL5C49
      *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
      G229-15 (CA5H) - G229-16 (CA5L) Cable disconnected from negative (-) battery terminal 54 to 69 Ω

      Tech Tips


      • If the resistance becomes normal (between 54 and 69 Ω) 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 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