DTC Troubleshooting: U0199
DTC U0199:
 Power Seat Control Unit Lost Communication with Door Multiplex Control Unit
  1. Clear the DTCs with the HDS.
  1. Turn the ignition switch to LOCK (0) and then back to ON (II).
  1. Wait for 6 seconds or more.
  1. Check for DTCs with the HDS.
Is DTC U0199 indicated?
YES -
Go to Step 5 .
NO -
Intermittent failure, the system is OK at this time. Check for loose or poor connections between the power seat control unit and the door multiplex control unit.■
  1. From the BODY ELECTRICAL system select menu, select UNIT INFORMATION, and then select CONNECTED UNIT.
Is the power window master switch (door multiplex control unit) detected?
YES -
Replace the power seat control unit .■
NO -
Go to Step 6 .
  1. Turn the ignition switch to LOCK (0).
  1. Disconnect the door multiplex control unit 37P connector.
  1. Disconnect power seat control unit connector A (40P).
  1. Check for continuity between power seat control unit connector A (40P) No. 39 and No. 40 terminals and the door multiplex control unit 37P connector No. 33 and No. 35 terminals individually.
Is there continuity?
YES -
Faulty door multiplex control unit.■
NO -
An open in the wire between the door multiplex control unit and the power seat control unit.■