CAN COMMUNICATION SYSTEM (for RHD with Entry and Start System), Diagnostic DTC:U1002

DTC Code DTC Name
U1002 Lost Communication with Gateway Module (MS Bus)

DESCRIPTION


DTC Code DTC Detection Condition Trouble Area
U1002 (CAN MS BUS) Lost communication with the gateway module (MS bus).
  • MS bus circuit

  • Main body ECU (multiplex network body ECU) CAN main wire or connector

  • Front power seat switch RH CAN branch wire or connector*1

  • Multiplex tilt and telescopic ECU CAN branch wire or connector*2

  • Driving support switch control ECU CAN branch wire or connector*3

  • Main body ECU (multiplex network body ECU)

  • Front power seat switch RH*1

  • Multiplex tilt and telescopic ECU*2

  • Driving monitor switch control ECU*3

  • No. 2 junction connector

  • No. 5 junction connector


WIRING DIAGRAM

A01DOWSE03

INSPECTION PROCEDURE

Tech Tips

Operating the engine switch, any switches or any doors triggers related ECU and sensor communication with the CAN, which causes resistance variation.

PROCEDURE


  1. DISCONNECT CABLE FROM NEGATIVE BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) battery terminal before measuring the resistances of the CAN main wire and the CAN branch wire.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the airbag system.

      Note


      • After turning the engine switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

      • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.


    NEXT
  2. CHECK CAN BUS WIRE (CHECK CAN MAIN WIRE FOR DISCONNECTION, CHECK BUS LINE FOR SHORT)


    1. A01DT5TE07
      Text in Illustration
      *a

      Component with harness connector

      (No. 5 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition Resistance: Malfunction
      G103-3 (CANP) - G103-2 (CANN) Engine switch off 54 to 69 Ω Below 53 Ω: Short in line
      G103-3 (CANP) - G103-2 (CANN) Engine switch off 54 to 69 Ω Higher than 70 Ω: Open in CAN main bus line
      G103-3 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher Below 6 kΩ: +B short
      G103-2 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher Below 6 kΩ: +B short
      G103-3 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher Below 200 Ω: Ground short
      G103-2 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher Below 200 Ω: Ground short
      Result
      Result Proceed to

      NG


      • Open in CAN main bus line

      A

      NG


      • Short in line

      • +B short

      • Ground short

      B
      OK C

    B
    C
    A
  3. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 JUNCTION CONNECTOR - MAIN BODY ECU)


    1. A01DOKME01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      Disconnect the G133 No. 2 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-4 (CANH) - G133-15 (CANL) Engine switch off 108 to 132 Ω

    NG
    OK
  4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 2 JUNCTION CONNECTOR - NO. 5 JUNCTION CONNECTOR)


    1. A01DOKME02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-6 (CANH) - G133-17 (CANL) Engine switch off 108 to 132 Ω

    NG
    OK
  5. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (MAIN BODY ECU - NO. 2 JUNCTION CONNECTOR)


    1. A01DPH0E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Main Body ECU [Multiplex Network Body ECU])

      Disconnect the G63 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G63-9 (CANP) - G63-10 (CANN) Engine switch off 108 to 132 Ω

    NG
    OK
  7. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  8. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 5 JUNCTION CONNECTOR - NO. 2 JUNCTION CONNECTOR)


    1. A01DS18E08
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 5 Junction Connector)

      Disconnect the G103 No. 5 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G103-3 (CANP) - G103-2 (CANN) Engine switch off 108 to 132 Ω

    NG
    OK
  9. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - FRONT POWER SEAT SWITCH RH)

    Note

    For vehicles without a seat position memory, go to "Check for Short in CAN Bus Wires (No. 2 Junction Connector - Multiplex Tilt and Telescopic ECU)".


    1. A01DU8RE95
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

      Disconnect the G133 No. 2 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-2 (CANH) - G133-13 (CANL) Engine switch off 200 Ω or higher
      G133-2 (CANH) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-13 (CANL) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-2 (CANH) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G133-13 (CANL) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  10. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - MULTIPLEX TILT AND TELESCOPIC ECU)

    Note

    For vehicles without a power tilt and power telescopic steering column, go to "Check for Short in CAN Bus Wires (No. 2 Junction Connector - Driving Support Switch Control ECU)".


    1. A01DU8RE96
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-3 (CANH) - G133-14 (CANL) Engine switch off 200 Ω or higher
      G133-3 (CANH) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-14 (CANL) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-3 (CANH) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G133-14 (CANL) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  11. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - DRIVING SUPPORT SWITCH CONTROL ECU)

    Note

    For vehicles without a multi-function switch, go to "Check for Short in CAN Bus Wires (No. 2 Junction Connector - Main Body ECU)".


    1. A01DU8RE97
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-5 (CANH) - G133-16 (CANL) Engine switch off 200 Ω or higher
      G133-5 (CANH) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-16 (CANL) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-5 (CANH) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G133-16 (CANL) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  12. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - MAIN BODY ECU)


    1. A01DU8RE98
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-4 (CANH) - G133-15 (CANL) Engine switch off 108 to 132 Ω
      G133-4 (CANH) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-15 (CANL) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-4 (CANH) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G133-15 (CANL) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 2 JUNCTION CONNECTOR - NO. 5 JUNCTION CONNECTOR)


    1. A01DU8RE99
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 2 Junction Connector)

      *b Front view of DLC3

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G133-6 (CANH) - G133-17 (CANL) Engine switch off 108 to 132 Ω
      G133-6 (CANH) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-17 (CANL) - G48-4 (CG) Engine switch off 200 Ω or higher
      G133-6 (CANH) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G133-17 (CANL) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  14. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  15. CHECK FOR SHORT IN CAN BUS WIRES (FRONT POWER SEAT SWITCH RH)


    1. A01DUJ7E01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Front Power Seat Switch RH)

      *b Front view of DLC3

      Disconnect the a5 front power seat switch RH connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      a5-8 (CANP) - a5-7 (CANN) Engine switch off 54 to 69 Ω
      a5-8 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
      a5-7 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
      a5-8 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      a5-7 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  16. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  17. CHECK FOR SHORT IN CAN BUS WIRES (MULTIPLEX TILT AND TELESCOPIC ECU)


    1. A01DN52E01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Multiplex Tilt and Telescopic ECU)

      *b Front view of DLC3

      Disconnect the G116 multiplex tilt and telescopic ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G116-5 (CANP) - G116-14 (CANN) Engine switch off 54 to 69 Ω
      G116-5 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
      G116-14 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
      G116-5 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G116-14 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  18. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  19. CHECK FOR SHORT IN CAN BUS WIRES (DRIVING SUPPORT SWITCH CONTROL ECU)


    1. for Automatic Transmission:


      1. A01DQ52E01
        Text in Illustration
        *a

        Front view of wire harness connector

        (to Driving Support Switch Control ECU)

        *b Front view of DLC3

        Disconnect the G163 driving support switch control ECU connector.

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        G163-2 (CANP) - G163-3 (CANN) Engine switch off 54 to 69 Ω
        G163-2 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
        G163-3 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
        G163-2 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
        G163-3 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher
    2. for Manual Transmission:


      1. A01DOLUE03
        Text in Illustration
        *a

        Rear view of wire harness connector

        (to Driving Support Switch Control ECU)

        *b Front view of DLC3

        Disconnect the G76 driving support switch control ECU connector.

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

        Standard Resistance
        Tester Connection Switch Condition Specified Condition
        G76-9 (CANP) - G76-10 (CANN) Engine switch off 54 to 69 Ω
        G76-9 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
        G76-10 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
        G76-9 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
        G76-10 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  20. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  21. CHECK FOR SHORT IN CAN BUS WIRES (MAIN BODY ECU)


    1. A01DTS1E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Main Body ECU [Multiplex Network Body ECU])

      *b Front view of DLC3

      Disconnect the G63 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G63-9 (CANP) - G63-10 (CANN) Engine switch off 108 to 132 Ω
      G63-9 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
      G63-10 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
      G63-9 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G63-10 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  22. CONNECT CONNECTOR


    1. Reconnect the G133 No. 2 junction connector.


    NEXT
  23. CHECK FOR SHORT IN CAN BUS WIRES (NO. 5 JUNCTION CONNECTOR)


    1. A01DS0KE12
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 5 Junction Connector)

      *b Front view of DLC3

      Disconnect the G103 No. 5 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      G103-3 (CANP) - G103-2 (CANN) Engine switch off 108 to 132 Ω
      G103-3 (CANP) - G48-4 (CG) Engine switch off 200 Ω or higher
      G103-2 (CANN) - G48-4 (CG) Engine switch off 200 Ω or higher
      G103-3 (CANP) - G48-16 (BAT) Engine switch off 6 kΩ or higher
      G103-2 (CANN) - G48-16 (BAT) Engine switch off 6 kΩ or higher

    NG
    OK
  24. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - BATTERY AND BODY GROUND)


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

      A01DPNHE03
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Main Body ECU [Multiplex Network Body ECU])

      *b

      Front view of wire harness connector

      (to Main Body ECU [Multiplex Network Body ECU])

      Note

      When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

    2. Remove the main body ECU (multiplex network body ECU) Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G63-3 (GND2) - Body ground Always Below 1 Ω
      A-11 (GND1) - Body ground Always Below 1 Ω
    4. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      A-30 (BECU) - Body ground Always 11 to 14 V
      A-31 (ALTB) - Body ground Always 11 to 14 V
      A-29 (ACC) - Body ground Engine switch on (ACC) 11 to 14 V
      A-32 (IG) - Body ground Engine switch on (IG) 11 to 14 V

    NG
    OK