Code B0056 indicates a fault in the third-row left seat belt sensor circuit. The restraint control module has detected an open, short, or out-of-range signal from the sensor that monitors buckle status for the left-side third-row seating position.
The hall-effect or reed switch inside the buckle assembly has failed open, shorted, or drifted out of specification.
Wires between the buckle sensor and restraint control module are chafed, cut, or shorted to power/ground, often at seat track pivot points.
The connector at the buckle, seat harness, or module has contaminated terminals, bent pins, or insufficient retention.
The buckle assembly is misaligned, the latch mechanism is worn, or foreign debris prevents proper sensor actuation.
The module's input circuit for this sensor has failed; this is rare and only considered after wiring and sensor are verified.
The restraint control module may disable the third-row left frontal or side curtain airbag deployment for that seating position while the fault is active. Other airbags remain functional.
Typically not. The sensor circuit is low-voltage and monitored by the restraint control module; a fuse loss would usually set a power-supply code rather than a sensor-specific code.
No. The module is the least likely cause. Most B0056 repairs involve the buckle sensor, its wiring, or connectors. Module replacement should only occur after thorough circuit verification.
Often yes. Access to the buckle connector and harness routing usually requires folding or removing the third-row seat cushion and trim panels.