OBD-II trouble code
B0092: Left Side Restraints Sensor 2 (Subfault)
A restraints module fault on the second-indexed left-side sensor circuit. This is the index where manufacturers diverge most — on some vehicles it is a side impact satellite, on others it belongs to occupant sensing entirely.
Quick facts
- System
- Body
- Category
- Airbag / SRS Restraints
- Severity
- High severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $120 – $800
- DIY difficulty
- Shop recommended
What does B0092 mean?
B0092 is logged by the restraints control module against the left-side sensor circuit it indexes as number two. What sits on the other end of that circuit is less settled than the code's generic title implies, and that ambiguity is the defining problem with this particular code.
On most applications it is what you would expect: a satellite impact sensor mounted out at the structure, one of two or three along the left side, reporting deformation to the module quickly enough to fire side protection. But B-codes are only loosely standardised, and on some manufacturers' vehicles this same code number is used in connection with occupant sensing — the seat-based system that decides whether a passenger is present, how heavy they are, and therefore whether and how forcefully to deploy. Those are different subsystems in different parts of the car with different parts, different test procedures and very different costs. Reading the generic definition and going straight to a door panel on a vehicle whose manufacturer meant a seat sensor is not a small detour; it is the wrong repair on the wrong component. Confirm the manufacturer's own definition for this code number on this model before anything else, and be suspicious of any advice found online that does not say which make it was written for.
Where B0092 genuinely is a side impact satellite, the middle index brings its own uncertainty. Vehicles are built with different numbers of side satellites — two per side is common, three occurs on larger vehicles and higher trims. On a two-sensor side, index two is the rearmost station. On a three-sensor side it is the middle one. The reliable way to settle it is to count the physical satellites on the car rather than to trust a generic table, because the same code number legitimately points at different places on two vehicles parked next to each other.
There is one further point that catches out competent technicians on restraints work generally, and it costs more repeat visits than any diagnostic error. Restraints circuits are specified within an extremely narrow resistance window — far narrower than an ordinary sensor circuit — because the module has to distinguish a healthy firing or sensing loop from a marginal one with high confidence and no second chance. That means a repair which would be entirely acceptable anywhere else on the vehicle can push the circuit out of specification. An added crimp, a butt connector, a section of splice wire of slightly different gauge, even a well-made solder joint adds resistance the module was not told to expect. This is precisely why manufacturers prohibit splicing into restraints harnesses and specify replacement of the complete pigtail or harness section instead. If this code was repaired once, passed a post-repair check, and returned a few days or weeks later, the most likely explanation is not that the diagnosis was wrong but that the repair method was — a marginal circuit sitting at the edge of the window drifts back outside it as the joint settles and oxidises.
As with every restraints fault the vehicle drives normally and the risk lies entirely in a collision that has not happened. Assume the affected protection is disabled, and have the system safely powered down before disconnecting anything, because these circuits are attached to pyrotechnic devices.
Common causes
- Fault at a satellite impact sensor on the left side, at whichever station this index designates
- Occupant sensing hardware or wiring on manufacturers that use this code number for the seat-based system
- Previous restraints wiring repaired with a splice or butt connector, pushing the circuit outside its narrow specified window
- Corroded terminals at a low-mounted connector in the rocker, B-pillar base or seat rail
- Water intrusion after a leak, a flood or a failed door vapour barrier
- Harness damaged where it passes under a seat and is worked by seat travel
- Sensor or module replaced without being configured to the vehicle
- Collision repair that disturbed the sensor mount or its harness routing
- Restraints control module fault, which should be concluded only after the circuit has been proven
Symptoms
- Airbag or SRS warning light on continuously
- B0092 stored in the restraints module alongside possible occupant sensing codes
- Side protection at the affected station disabled by the module
- Passenger airbag status indicator behaving oddly on vehicles where this code relates to occupant sensing
- Code returning days or weeks after a wiring repair that initially appeared successful
- No effect on engine operation, drivability or handling
- Fault appearing after flooding, a deep puddle or a leaking door seal
Diagnostic steps
- 1.Establish the manufacturer's own definition of B0092 for this exact make and model first, since some makers use this code number for occupant sensing rather than for a side impact satellite and the two lead to completely different repairs.
- 2.Count the physical side satellites fitted on this vehicle to determine whether index two is the rear station on a two-sensor side or the middle station on a three-sensor side.
- 3.Read the complete restraints module code set, since companion codes at other indices change the interpretation substantially.
- 4.Ask whether this circuit has been repaired before, and if so how — a splice or butt connector in a restraints harness is a leading cause of a fault that returns after an apparently successful fix.
- 5.Power the restraints system down per the manufacturer's procedure and observe the specified wait time before disconnecting anything.
- 6.Measure the circuit against the manufacturer's specified resistance window rather than simply checking for continuity, because these circuits are specified far more tightly than ordinary sensor circuits and a circuit that conducts can still be out of range.
- 7.Inspect low-mounted connectors in the rocker, B-pillar base and seat rail for corrosion and water staining.
- 8.Where the circuit passes under a seat, check it through the seat's full travel for pinching and abrasion.
- 9.Replace the complete pigtail or specified harness section rather than splicing, in line with the manufacturer's requirement.
- 10.Configure any replaced component to the vehicle, clear the codes, and confirm the light stays out across several ignition cycles rather than just one.
Repair cost
$120 – $800
Diagnosis is $120 to $220 and needs restraints module access. A satellite sensor is $80 to $300 in parts and $250 to $650 fitted. If the code turns out to relate to occupant sensing on your make, the picture changes considerably — a seat occupancy sensor or weight sensing mat is often $200 to $600 in parts with the seat cushion or the whole seat requiring removal, taking the job to $500 to $1,100, which is exactly why confirming the definition before quoting matters. Budget for a complete pigtail or harness section rather than a splice repair, because manufacturers prohibit splicing here and a spliced circuit is the usual reason this code comes back.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with airbag / srs crash sensor replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
Leave this one to a qualified shop. It typically involves emissions-critical components, refrigerant handling, or other work that requires manufacturer-grade tooling, training, or certification. DIY attempts often produce a more expensive problem than the original code.