CAN COMMUNICATION SYSTEM (for RHD), Diagnostic DTC:U1002

DTC Code DTC Name
U1002 Lost Communication with Gateway Module

DESCRIPTION


DTC Code DTC Detection Condition Trouble Area
U1002 Lost communication with gateway module (WIL bus)
  • WIL bus circuit

  • Active headrest control ECU RH (front seat headrest assembly RH) CAN main wire or connector

  • Active headrest control ECU LH (front seat headrest assembly LH) CAN main wire or connector*1

  • Network gateway ECU CAN branch wire or connector

  • Active headrest control ECU RH (front seat headrest assembly RH)

  • Active headrest control ECU LH (front seat headrest assembly LH)*1

  • Network gateway ECU

  • No. 13 junction connector

  • No. 16 junction connector*2


WIRING DIAGRAM

A01H20HE05

INSPECTION PROCEDURE

Tech Tips

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

PROCEDURE


  1. PRECAUTION

    Note

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


    NEXT
  2. DISCONNECT CABLE FROM NEGATIVE AUXILIARY BATTERY TERMINAL


    1. Disconnect the cable from the negative (-) auxiliary 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 (-) auxiliary battery terminal to disable the SRS system.

      Note

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


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


    1. A01H0RWE02
      Text in Illustration
      *a

      Component with harness connected

      (Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])

      *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
      e60-2 (CA3H) - e60-5 (CA3L) Power switch off 54 to 69 Ω Below 53 Ω: Short in line
      e60-2 (CA3H) - e60-5 (CA3L) Power switch off 54 to 69 Ω Higher than 70 Ω: Open in CAN main bus line
      e60-2 (CA3H) - L31-16 (BAT) Power switch off 6 kΩ or higher Below 6 kΩ: +B short
      e60-5 (CA3L) - L31-16 (BAT) Power switch off 6 kΩ or higher Below 6 kΩ: +B short
      e60-2 (CA3H) - e60-1 (GND) Power switch off 200 Ω or higher Below 200 Ω: Ground short
      e60-5 (CA3L) - e60-1 (GND) Power switch off 200 Ω or higher Below 200 Ω: Ground short
      Result
      Result Proceed to

      NG


      • Open in CAN main wire

      A

      NG


      • Short in line

      • +B short

      • Ground short

      B
      OK C

    B
    C
    A
  4. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)


    1. A01GX91E95
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 Junction Connector)

      Disconnect the No. 13 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L120-3 (CANH) - L120-14 (CANL) Power switch off 108 to 132 Ω
      Result
      Result Proceed to
      OK (for 5-Passenger with Ottoman) A
      OK (except 5-Passenger with Ottoman) B
      NG C

    B
    C
    A
  5. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU LH)


    1. A01GX91E96
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L120-2 (CANH) - L120-13 (CANL) Power switch off 108 to 132 Ω

    NG
    OK
  6. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR)


    1. A01GX91E96
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 Junction Connector)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L120-2 (CANH) - L120-13 (CANL) Power switch off 108 to 132 Ω

    NG
    OK
  7. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  8. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU RH)


    1. A01H19HE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])

      Disconnect the active headrest control ECU RH (front seat headrest assembly RH) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e60-2 (CA3H) - e60-5 (CA3L) Power switch off 108 to 132 Ω

    NG
    OK
  9. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  10. CHECK FOR OPEN IN CAN BUS MAIN WIRE (ACTIVE HEADREST CONTROL ECU LH)


    1. A01H19HE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH])

      Disconnect the active headrest control ECU LH (front seat headrest assembly LH) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e73-2 (CA3H) - e73-5 (CA3L) Power switch off 108 to 132 Ω

    NG
    OK
  11. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  12. CHECK FOR OPEN IN CAN BUS MAIN WIRE (NO. 16 JUNCTION CONNECTOR)


    1. A01GYRNE09
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 16 Junction Connector)

      Disconnect the No. 16 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e111-3 (CA3H) - e111-2 (CA3L) Power switch off 108 to 132 Ω

    NG
    OK
  13. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NETWORK GATEWAY ECU)


    1. A01GY1LE58
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 Junction Connector)

      *b Front view of DLC3

      Disconnect the No. 13 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L120-1 (CANH) - L120-12 (CANL) Power switch off 108 to 132 Ω
      L120-1 (CANH) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-12 (CANL) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-1 (CANH) - L31-16 (BAT) Power switch off 6 kΩ or higher
      L120-12 (CANL) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  14. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU RH)


    1. A01GY1LE31
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 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
      L120-3 (CANH) - L120-14 (CANL) Power switch off 108 to 132 Ω
      L120-3 (CANH) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-14 (CANL) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-3 (CANH) - L31-16 (BAT) Power switch off 6 kΩ or higher
      L120-14 (CANL) - L31-16 (BAT) Power switch off 6 kΩ or higher
      Result
      Result Proceed to
      OK (for 5-Passenger with Ottoman) A
      OK (except 5-Passenger with Ottoman) B
      NG C

    B
    C
    A
  15. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - ACTIVE HEADREST CONTROL ECU LH)


    1. A01GY1LE30
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 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
      L120-2 (CANH) - L120-13 (CANL) Power switch off 200 Ω or higher
      L120-2 (CANH) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-13 (CANL) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-2 (CANH) - L31-16 (BAT) Power switch off 6 kΩ or higher
      L120-13 (CANL) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  16. CHECK FOR SHORT IN CAN BUS WIRES (NO. 13 JUNCTION CONNECTOR - NO. 16 JUNCTION CONNECTOR)


    1. A01GY1LE30
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 13 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
      L120-2 (CANH) - L120-13 (CANL) Power switch off 200 Ω or higher
      L120-2 (CANH) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-13 (CANL) - L31-4 (CG) Power switch off 200 Ω or higher
      L120-2 (CANH) - L31-16 (BAT) Power switch off 6 kΩ or higher
      L120-13 (CANL) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  17. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  18. CHECK FOR SHORT IN CAN BUS WIRES (NETWORK GATEWAY ECU)


    1. A01GX97E01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Network Gateway ECU)

      *b Front view of DLC3

      Disconnect the network gateway ECU connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      L102-13 (CA2H) - L102-12 (CA2L) Power switch off 54 to 69 Ω
      L102-13 (CA2H) - L31-4 (CG) Power switch off 200 Ω or higher
      L102-12 (CA2L) - L31-4 (CG) Power switch off 200 Ω or higher
      L102-13 (CA2H) - L31-16 (BAT) Power switch off 6 kΩ or higher
      L102-12 (CA2L) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  19. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  20. CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU RH)


    1. A01GZSQE02
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Active Headrest Control ECU RH [Front Seat Headrest Assembly RH])

      *b Front view of DLC3

      Disconnect the headrest control ECU RH (front seat headrest assembly RH) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e60-2 (CA3H) - e60-5 (CA3L) Power switch off 108 to 132 Ω
      e60-2 (CA3H) - L31-4 (CG) Power switch off 200 Ω or higher
      e60-5 (CA3L) - L31-4 (CG) Power switch off 200 Ω or higher
      e60-2 (CA3H) - L31-16 (BAT) Power switch off 6 kΩ or higher
      e60-5 (CA3L) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  21. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  22. CHECK FOR SHORT IN CAN BUS WIRES (ACTIVE HEADREST CONTROL ECU LH)


    1. A01GZSQE01
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to Active Headrest Control ECU LH [Front Seat Headrest Assembly LH])

      *b Front view of DLC3

      Disconnect the headrest control ECU LH (front seat headrest assembly LH) connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e73-2 (CA3H) - e73-5 (CA3L) Power switch off 108 to 132 Ω
      e73-2 (CA3H) - L31-4 (CG) Power switch off 200 Ω or higher
      e73-5 (CA3L) - L31-4 (CG) Power switch off 200 Ω or higher
      e73-2 (CA3H) - L31-16 (BAT) Power switch off 6 kΩ or higher
      e73-5 (CA3L) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  23. CONNECT CONNECTOR


    1. Reconnect the L120 No. 13 junction connector.


    NEXT
  24. CHECK FOR SHORT IN CAN BUS WIRES (NO. 16 JUNCTION CONNECTOR)


    1. A01H03GE08
      Text in Illustration
      *a

      Rear view of wire harness connector

      (to No. 16 Junction Connector)

      *b Front view of DLC3

      Disconnect the No. 16 junction connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      e111-3 (CA3H) - e111-2 (CA3L) Power switch off 108 to 132 Ω
      e111-3 (CA3H) - L31-4 (CG) Power switch off 200 Ω or higher
      e111-2 (CA3L) - L31-4 (CG) Power switch off 200 Ω or higher
      e111-3 (CA3H) - L31-16 (BAT) Power switch off 6 kΩ or higher
      e111-2 (CA3L) - L31-16 (BAT) Power switch off 6 kΩ or higher

    NG
    OK
  25. CHECK HARNESS AND CONNECTOR (NETWORK GATEWAY ECU - BATTERY AND BODY GROUND)


    1. A01GZ2LE01
      Text in Illustration
      *a

      Front view of wire harness connector

      (to Network Gateway ECU)

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

      Note

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

    2. Disconnect the network gateway ECU connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      L102-10 (IG1) - Body ground Power switch on (IG) 11 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      L102-4 (GND) - Body ground Always Below 1 Ω

    NG
    OK