CAN COMMUNICATION SYSTEM, Diagnostic DTC:U0209

DTC Code DTC Name
U0209 Lost Communication with "Seat Control Module B"

DESCRIPTION

DTC No. DTC Detection Condition Trouble Area
U0209
  • No communication from the front power seat switch RH continues (for LHD).

  • No communication from the front power seat switch LH continues (for RHD).


  • Front power seat switch RH branch wire or connector (for LHD)

  • Power source circuit of front power seat switch RH (for LHD)

  • Front power seat switch RH (for LHD)

  • Front power seat switch LH branch wire or connector (for RHD)

  • Power source circuit of front power seat switch LH (for RHD)

  • Front power seat switch LH (for RHD)

WIRING DIAGRAM

A01NE0NE03
A01NGB9E03

INSPECTION PROCEDURE

Note


  • Turn the power switch off before measuring the resistances between CAN bus main wires and between CAN bus branch wires.

  • Turn the power switch off before inspecting CAN bus wires for a ground short.

  • After the power switch is turned off, check that the key reminder warning system and light reminder warning system are not operating.

  • Before measuring the resistance, leave the vehicle as is for at least 1 minute and do not operate the power switch, any other switches or the doors. If any doors need to be opened in order to check connectors, open the doors and leave them open.

Tech Tips


  • Operating the power switch, any other switches or a door triggers related ECU and sensor communication on the CAN. This communication will cause the resistance value to change.

  • Even after DTCs are cleared, if a DTC is stored again after driving the vehicle for a while, the malfunction may be occurring due to vibration of the vehicle. In such a case, wiggling the ECUs or wire harness while performing the inspection below may help determine the cause of the malfunction.

PROCEDURE


  1. RECONFIRM DTC OUTPUT


    1. Reconfirm DTCs.

      Tech Tips

      If CAN MS bus DTC U1002 is output from the main body ECU (Intelligent tester display/Main Body), troubleshoot for U1002 and check for malfunctions in the CAN MS bus circuit.

      Result
      Result Proceed to

      U1002 is not output from main body ECU (Intelligent tester display/Main Body)

      (for LHD)

      A

      U1002 is not output from main body ECU (Intelligent tester display/Main Body)

      (for RHD)

      B
      U1002 is output from main body ECU (Intelligent tester display/Main Body) C

    B
    C
    A
  2. CHECK CAN BUS WIRE FOR DISCONNECTION (FRONT POWER SEAT SWITCH RH BRANCH WIRE)


    1. Turn the power switch off.

    2. A01NGLNE11
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch RH)

      Disconnect the Z25 front power seat switch RH connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      Z25-8 (CANP) - Z25-7 (CANN) Power switch off 54 to 69 Ω

    NG
    OK
  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. A01NE20E08
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch RH)

      Disconnect the Z26 front power seat switch RH connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      Z26-6 (+B) - Body ground Always 11 to 14 V

    NG
    OK
  4. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)


    1. A01NE20E09
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch RH)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Z26-1 (GND) - Body ground Always Below 1 Ω

    NG
    OK
  5. CHECK CAN BUS WIRE FOR DISCONNECTION (FRONT POWER SEAT SWITCH LH BRANCH WIRE)


    1. Turn the power switch off.

    2. A01NGLNE08
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch LH)

      Disconnect the a8 front power seat switch LH connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      a8-8 (CANP) - a8-7 (CANN) Power switch off 54 to 69 Ω

    NG
    OK
  6. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)


    1. A01NE20E05
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch LH)

      Disconnect the a9 front power seat switch LH connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      a9-6 (+B) - Body ground Always 11 to 14 V

    NG
    OK
  7. CHECK HARNESS AND CONNECTOR (GROUND TERMINAL)


    1. A01NE20E06
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Front Power Seat Switch LH)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      a9-1 (GND) - Body ground Always Below 1 Ω

    NG
    OK