Airbags (SRS)

B0051 Passenger seatbelt sensor: circuit fault

By: Diagno editorial team · Updated: 2026-10-15

B0051 means: Passenger seatbelt sensor: circuit fault. The airbag system (SRS) found a fault in an airbag, seatbelt pretensioner, sensor or their wiring. Drive gently and have the car checked soon. The repair usually costs about €60–700 in Estonia. The most common cause: connector under the seat loose or corroded.

Is it safe to drive?Get it checked soonDrive gently and have the car checked soon.

Typical repair cost€60–700parts and labour in Estonia

What it means

The airbag system (SRS) found a fault in an airbag, seatbelt pretensioner, sensor or their wiring. While the light is on, an airbag may not deploy in a crash.

What you may notice

Airbag light on
Seatbelt pretensioner may not work

What could be wrong

1Connector under the seat loose or corroded
2Worn steering wheel clock spring
3Open airbag or pretensioner circuit
4Crash sensor or module

Repair difficulty: Moderate

What you can check yourself

Don't poke at airbag connectors with the ignition on. Check that the connectors under the seats are clipped in. Best left to a workshop. It needs a diagnostic tool and experience.

How we fix it

We read the airbag module codes
We measure the circuit resistance safely
We replace the clock spring, connector or part and clear the fault

Standard SAE description: Passenger Seatbelt Sensor

This code usually comes with: Airbag lightSee what the light means →Check the fuse · If a light, the horn, wipers, a socket or the fuel pump is dead, a blown fuse may be the cause.Fuse boxes by car →

Want a definite answer?

Bring the car to our workshop in Estonia for diagnostics. We read the fault codes, test the sensors and tell you what is wrong. Repair price depends on the work involved, generally €45 per hour.

Book a diagnostic check

Questions

What does fault code B0051 mean?

Passenger seatbelt sensor: circuit fault. The airbag system (SRS) found a fault in an airbag, seatbelt pretensioner, sensor or their wiring. While the light is on, an airbag may not deploy in a crash.

Can I drive with code B0051?

Drive gently and have the car checked soon.

How much does it cost to fix B0051?

Roughly €60–700 in Estonia. The price depends on exactly what has failed and on the car.

How is B0051 fixed?

We read the airbag module codes. We measure the circuit resistance safely. We replace the clock spring, connector or part and clear the fault.

Based on AI combined with our hands-on workshop experience and knowledge. This information is general and prices are approximate (Estonian workshop rates). The same code can mean different things on different cars. Only an inspection of the car gives a definite answer.