DTC Troubleshooting: B1827
  1. Measure the voltage between the rear up-down motor/position sensor 5P connector No. 5 (+) and No. 4 (−) terminals.
Is there about 5 V?
YES -
Faulty rear up-down motor/position sensor, replace the seat frame assembly.■
NO -
If there is no voltage, replace the power seat control unit. If there is battery voltage, repair a short in the wire (sensor line).■
  1. Turn the ignition switch to LOCK (0).
  1. Disconnect power seat control unit connector A (40P).
  1. Disconnect the rear up-down motor/position sensor 5P connector.