CAN COMMUNICATION SYSTEM, Diagnostic DTC:U0208

DTC Code DTC Name
U0208 Lost Communication with "Seat Control Module A"

DESCRIPTION

DTC No. Detection Item DTC Detection Condition Trouble Area DTC Output from
U0208 Lost Communication with "Seat Control Module A" There is no communication from the front power seat switch.

  • Power source circuit of front power seat switch (for driver side)

  • Front power seat switch (for driver side) ground circuit

  • Front power seat switch (for driver side) CAN branch wire or connector

  • Front power seat switch (for driver side)

 Main body ECU (multiplex network body ECU)

WIRING DIAGRAM

Figure 1. for LHD:

B0057N9E56

Figure 2. for RHD:

B0057N9E57

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, 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 battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work.

    Click here

  • Some parts must be initialized and set when replacing or removing and installing parts.

    Click here

  • Inspect the fuses for circuits related to this system before performing the following inspection procedure.

  • 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 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


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

  • 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. CHECK FOR DTC


    1. Check for DTCs.


      Body Electrical > Main Body > Trouble Codes

      Tech Tips

      If DTC U1002 is output from the gateway of the main body ECU (multiplex network body ECU), this indicates a sub bus 1 malfunction. Troubleshoot for DTC U1002 and check for malfunctions in sub bus 1.

      Result
      Result Proceed to
      DTC U1002 is not output from main body ECU (multiplex network body ECU) A
      DTC U1002 is output from main body ECU (multiplex network body ECU) B

    B

    GO TO DIAGNOSIS PROCEDURE INDICATED BY OUTPUT DTC Click here

    A

  2. CHECK FOR OPEN IN CAN BUS WIRE (FRONT POWER SEAT SWITCH [FOR DRIVER SIDE] BRANCH WIRE)


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

    2. B0057KQC04
      *A for RHD
      *B for LHD
      *a

      Front view of wire harness connector

      (to Front Power Seat Switch [for Driver Side])

      Disconnect the front power seat switch (for driver side) connector.

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

      Standard Resistance
      for RHD
      Tester Connection Condition Specified Condition
      f7-8 (CANP) - f7-7 (CANN) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      for LHD
      Tester Connection Condition Specified Condition
      g12-8 (CANP) - g12-7 (CANN) Cable disconnected from negative (-) battery terminal 54 to 69 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE CAN BRANCH WIRE OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)


    1. Disconnect the front power seat switch (for driver side) connector.

    2. B005B7XC11
      *A for RHD
      *B for LHD
      *a

      Front view of wire harness connector

      (to Front Power Seat Switch [for Driver Side])

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

      Standard Resistance
      for RHD
      Tester Connection Condition Specified Condition
      f6-2 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω
      for LHD
      Tester Connection Condition Specified Condition
      g11-2 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω

    3. Reconnect the cable to the negative (-) battery terminal.

      Note

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

      Click here

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

      Standard Voltage
      for RHD
      Tester Connection Condition Specified Condition
      f6-7 (+B) - Body ground Always 11 to 14 V
      f7-12 (SYSB) - Body ground Always 11 to 14 V
      f7-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Engine switch off Below 1 V
      for LHD
      Tester Connection Condition Specified Condition
      g11-7 (+B) - Body ground Always 11 to 14 V
      g12-12 (SYSB) - Body ground Always 11 to 14 V
      g12-3 (IG) - Body ground Engine switch on (IG) 11 to 14 V
      Engine switch off Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT POWER SEAT SWITCH (FOR DRIVER SIDE) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)