Faulty or dirty passenger seat belt buckle switch or sensor; Damaged, corroded or loose connector under the passenger seat; Chafed, stretched or broken wiring from seat movement or items stored under the seat; Debris or liquid in the buckle mechanism giving a false reading; Poor repair after a previous collision or seat removal, such as a wrong or unplugged connector; Fault inside the restraint control module.

B0052

Passenger Seat Belt Sensor.

Generic
Body
Generic code
Medium severity

How this code is built

B: SystemBody
0: Defined bySAE, the same on every car
0: AreaBody area 0
52: FaultThe specific fault in that area

What it means

B0052 is the generic code for a fault in the passenger seat belt sensor circuit, which is normally the buckle switch that tells the restraint control module whether the belt is fastened. The module sets the code when the signal is open circuit, shorted, out of range or implausible. Exact wiring and sensor type vary by make and model, so check model-specific data.

Symptoms

Airbag or SRS warning light on
Passenger seat belt warning light or chime stays on or does not work
Passenger airbag status indicator behaves oddly
Seat belt warning chime sounds with the belt fastened or with an empty seat
Fault may come and go when the seat is moved or bumped

Possible causes

Faulty or dirty passenger seat belt buckle switch or sensorlikely
Damaged, corroded or loose connector under the passenger seatlikely
Chafed, stretched or broken wiring from seat movement or items stored under the seatlikely
Debris or liquid in the buckle mechanism giving a false readingpossible
Poor repair after a previous collision or seat removal, such as a wrong or unplugged connectorpossible
Fault inside the restraint control modulerare

How to diagnose

Read all stored and pending codes and note freeze frame data, checking for other SRS or occupancy codes
Check the seat belt warning light and see if the fault appears when the belt is fastened and unfastened
Inspect the buckle for debris, spills or damage and check it latches firmly
Inspect the passenger seat connector and wiring under the seat for damage, corrosion, pin tension and routing, following the manufacturer's SRS safety procedure
With the correct procedure, read live data and watch the belt status change as the buckle is latched and released
Test the circuit for continuity, short circuits and resistance values only as the manufacturer specifies, without probing airbag connectors directly
Check for known service bulletins for your model, then clear the code and retest to see if it returns

How to fix

Replace the faulty buckle assembly or sensor
Repair or replace damaged wiring and renew any corroded or damaged connector
Clean the buckle if contamination is the cause, then recheck operation
Correct any incorrect connections or routing from earlier repairs
Replace or repair the restraint control module only after wiring and sensor faults are ruled out, as the manufacturer specifies

Can I keep driving?

Medium severity

The car can usually be driven, but the passenger restraint system may not work as designed, so book a repair soon. Avoid carrying a passenger in that seat until it is fixed.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.