Airbags

B0081 — Passenger Occupant Classification Sensor Fault

Severity: medium Safe to drive

What B0081 means

The airbag (SRS) control module relies on a passenger sensing system in the front seat to tell whether someone is seated and how heavy they are. That information decides whether the passenger airbag is enabled and how it deploys. B0081 is stored when the signal from the sensor or module is missing, implausible, or fails self-test.

Symptoms

  • Airbag / SRS warning light on
  • Passenger Airbag Off indicator lit
  • Warning that comes and goes
  • Indicator does not match whether someone is in the seat

Possible causes

  1. Faulty passenger sensor or module (seat mat)
  2. Open, short or poor connection in the wiring harness
  3. Loose or corroded connector under the seat
  4. Wrong part installed or calibration not performed after replacement
  5. Aftermarket seat cover or objects altering the seat load
  6. Failed SRS control module (unlikely)

How to diagnose

  1. Scan for codes with an SRS-capable tool, note any other codes, clear and see if B0081 returns
  2. Check for aftermarket seat covers, heaters or cushions, and for items stored under the seat
  3. Disconnect the battery and wait per the manufacturer's procedure, then inspect connectors and harness under the passenger seat
  4. Confirm the connector is fully latched and the terminals are clean and not bent
  5. Inspect the harness for chafing, breaks and shorts to ground, especially where it flexes with seat movement
  6. View occupant sensor data on a scan tool with the seat empty and loaded
  7. Test circuit power and resistance per the factory wiring diagram
  8. After repair, perform the required calibration or relearn and clear the code

Common fixes

  • Reseat or replace the connector and clean the terminals
  • Repair the damaged wiring harness
  • Replace the passenger sensor or module and calibrate it
  • Remove the aftermarket cover or other interference
  • Replace or reprogram the SRS module if confirmed faulty

Questions and answers

Can I drive with B0081?

Yes, the car will still run normally. But the passenger airbag may not work properly in a crash, so have it diagnosed soon.

Why did B0081 appear after I installed a seat cover?

The sensor in the seat measures load, and a thick or aftermarket cover can distort the reading. Remove the cover, clear the code and see if it returns.

Can I just clear B0081 myself?

You can with an SRS-capable scanner, but the code will return if the cause remains. Check the connector and wiring under the seat first.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.