Body, generic

B00C3 Passenger Seat Occupant Classification Sensor D

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

B00C3 is the fourth passenger seat classification input. No carmaker documents it under this number. Some classification signals are not a weight at all but a frequency, which makes them prone to electrical noise. Tesla reported for 2017–2019 Model 3 cars that the OCS frequency could leave its valid range because of interference on the passenger seat harness, so the airbag symbol appeared on the touchscreen. The first fix added a harness extension with a ferrite filter at the OCS module, which sits under the front of the seat; a later bulletin used a dedicated filter module, each about 0.15 h of labour. Whether a maker files such a signal as D is not known. A stored B00C3 means this input is missing or out of range, and the airbag lamp stays on until the cause is found.

Likely causes

Electrical interference coupled into the seat harness (seat heating, motors, routing near other leads)
Harness under tension or plug loose at the classification module when the seat moves
Internal fault of sensor D or the classification module

Symptoms

  • Airbag warning lamp or airbag symbol on the display
  • Fault may depend on seat position or on other electrical loads being switched on
  • Safety note: occupant classification unreliable; work on seat wiring only de-energised (12 V off, wait time), use the maker's filter or rework kit where one exists, specialist workshop only

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€60–800
Time0.3–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

passenger classification sensor dsrs seat wiringoccupant classification module

Related codes

B00C2B00C4B00A0B00B3

References: static.nhtsa.gov, static.nhtsa.gov.