B0001 — Driver frontal airbag — stage 1 deployment control

B0001 identifies the stage 1 circuit of the driver's frontal airbag. The full subcode matters: excessive resistance, an electrical short and crossed circuits require different fault paths. It does not establish that the airbag itself needs replacement. Jaguar and GM examples below concern the vehicles listed in those bulletins; they are not universal repair instructions.

Affected system: Supplemental restraint system (SRS)

Symptoms

• Airbag warning lamp or a restraint-system service message.
• An intermittent warning may occur with steering-wheel movement on vehicles affected by the cited contact faults.

Possible causes

• Poor connections in the stage 1 airbag wiring or steering-wheel clock-spring path, where fitted.
• A short, excessive or insufficient circuit resistance, distinguished by the complete DTC suffix.
• For the GM vehicles in 21-NA-005, contamination at the inflator connection can produce resistance spikes.

What to check

• Read the complete B0001 suffix from the SRS/RCM module; a generic engine-code reader may omit the useful detail.
• Confirm stage 1 and the affected circuit in the exact vehicle documentation before choosing a test.
• A qualified SRS technician can inspect recorded deployment-circuit data. Variation linked to steering movement directs attention to the connection path; it does not by itself identify a failed part.
• Have connector retention and the clock-spring path checked under the manufacturer's SRS deactivation procedure. Do not probe the inflator or attach a test lamp/multimeter to its firing terminals.
• After the confirmed repair, run the prescribed SRS self-test and check whether the original suffix returns.

Also written as: B0001-00, B000100, BO001 (some scan tools add the fault-type byte, e.g. -00).