A faulty passenger seat weight sensor (Sensor D) or its internal strain gauge.; Damaged or pinched wiring in the seat harness, often due to seat movement or objects caught under the seat.; Corroded or loose electrical connector at the OCS module or under the passenger seat.; A failed Occupant Classification System module (OCS module) that cannot process the sensor signal.; Physical damage to the seat cushion or sensor mat from spills, heavy loads, or seat compression.; Improper previous repair or aftermarket seat cover interfering with the sensor mat.; Software calibration drift in the OCS module requiring recalibration.

DTC codes / B00xx · Airbags, seats, doors, lights and comfort systems / B00C3

B00C3Passenger Seat Occupant Classification Sensor D

Q: What does code B00C3 mean?

Passenger Seat Occupant Classification Sensor D. B00C3 indicates that the Occupant Classification System (OCS) module has detected a fault with the passenger seat weight sensor designated as Sensor D, which is part of the system that determines whether the front passenger seat is occupied and how much the occupant weighs. The computer compares the signal from Sensor D against expected values and sets this code when the signal is out of range, erratic, or missing entirely.

B00C3 indicates that the Occupant Classification System (OCS) module has detected a fault with the passenger seat weight sensor designated as Sensor D, which is part of the system that determines whether the front passenger seat is occupied and how much the occupant weighs. The computer compares the signal from Sensor D against expected values and sets this code when the signal is out of range, erratic, or missing entirely.

SystemBody

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaAirbags, seats, doors, lights and comfort systems

Symptoms you may notice

The airbag warning light on the instrument cluster is illuminated, often with no other noticeable symptoms.
The passenger airbag may be automatically disabled even when an adult is seated in the passenger seat.
The passenger seatbelt reminder chime may not activate when someone sits in the passenger seat.
The passenger airbag status indicator may show 'off' or 'disabled' regardless of seat occupancy.
In some vehicles, a message such as 'Passenger Airbag Off' or 'Service Airbag System' appears on the driver information center.
The remote start feature may be disabled as a safety precaution in certain models.

Common causes, most likely first

A faulty passenger seat weight sensor (Sensor D) or its internal strain gauge.
Damaged or pinched wiring in the seat harness, often due to seat movement or objects caught under the seat.
Corroded or loose electrical connector at the OCS module or under the passenger seat.
A failed Occupant Classification System module (OCS module) that cannot process the sensor signal.
Physical damage to the seat cushion or sensor mat from spills, heavy loads, or seat compression.
Improper previous repair or aftermarket seat cover interfering with the sensor mat.
Software calibration drift in the OCS module requiring recalibration.

How to diagnose and fix it

Inspect the passenger seat area for any objects, spills, or damage that could affect the weight sensor and clean or remove them.
Check the under-seat wiring harness and connectors for chafing, pinching, or corrosion, and repair any damaged wires or terminals.
Use a scan tool to read live data from the OCS module and observe the Sensor D weight reading while pressing on the seat to see if the signal changes smoothly.
Perform a resistance or voltage test on the Sensor D circuit according to the manufacturer's service information to isolate a sensor or wiring fault.
If the sensor is faulty, replace the passenger seat weight sensor mat or sensor assembly as required.
After repair, recalibrate the Occupant Classification System using a scan tool and follow the manufacturer's zero-point calibration procedure.
Clear the diagnostic trouble codes and verify that the airbag warning light is off and the passenger airbag status operates correctly with a known weight on the seat.

What Most Techs Miss on B00C3

A common oversight is replacing the OCS module when the actual fault is a chafed wire under the seat that only loses connection when the seat is moved, so always wiggle-test the harness while watching live data.
The weight sensor mat can be damaged by liquid spills that are not immediately obvious, and the resulting corrosion may not show up until months later, so inspect the seat cushion for stains or stiffness.
After any repair involving the passenger seat, the OCS must be recalibrated with a scan tool; skipping this step will cause the code to return even if all components are good.
Some vehicles require the battery to be disconnected and the seat removed to access the sensor, and failing to follow the proper safety procedure can damage the OCS module or set additional codes.
A weak or failing battery can cause erratic OCS behavior and set B00C3, so always check battery voltage and charging system health before condemning the sensor.

Can I keep driving with B00C3?

You can generally drive the vehicle with this code, but the passenger airbag may not deploy in a crash, so avoid carrying passengers in the front seat until the fault is repaired. Have the system diagnosed promptly to restore full airbag protection.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.