Damaged, loose or corroded connector at the left curtain airbag or in the A, B or C pillar; Wiring fault in the left curtain circuit (open circuit, short to earth or short to voltage), often from chafing at the pillar or door shut; Faulty left curtain airbag module or its igniter (squib) with out-of-range resistance; Damaged or disturbed clockspring-style or inline connector following trim, headlining or seat removal; Incorrectly refitted or non-matching airbag after previous repair or accident work; Faulty restraint control module output driver; Water ingress or corrosion in the roof rail or pillar area.

B0022

Left Curtain Deployment Control 2.

Generic
Body
Generic code
High severity

How this code is built

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

What it means

B0022 is defined here as Left Curtain Deployment Control 2, a fault in the control circuit for the left-hand curtain airbag (or its second stage or squib circuit). The restraint control module checks the deployment circuit when the ignition is switched on and while driving. It set the code because it saw a resistance, voltage or continuity reading outside the expected range. Exact circuit layout and the meaning of 'control 2' vary by manufacturer and model.

Symptoms

Airbag warning light on the dashboard
Airbag light stays on after start-up, or flashes
Left curtain airbag may not deploy in a crash
Other airbag codes stored alongside it
Failed MOT or inspection because of the SRS warning light

Possible causes

Damaged, loose or corroded connector at the left curtain airbag or in the A, B or C pillarlikely
Wiring fault in the left curtain circuit (open circuit, short to earth or short to voltage), often from chafing at the pillar or door shutlikely
Faulty left curtain airbag module or its igniter (squib) with out-of-range resistancepossible
Damaged or disturbed clockspring-style or inline connector following trim, headlining or seat removalpossible
Incorrectly refitted or non-matching airbag after previous repair or accident workpossible
Faulty restraint control module output driverrare
Water ingress or corrosion in the roof rail or pillar arearare

How to diagnose

Read all stored and pending codes and note whether B0022 is current or history, plus any related airbag codes and the freeze frame data
Ask about recent work such as headlining, trim, seat, windscreen or accident repairs that could have disturbed the circuit
Make sure the vehicle's battery is disconnected and the manufacturer's wait time has passed before touching any airbag connector
Visually inspect the left curtain airbag connector and any inline connectors for damage, bent pins, loose locking tabs or corrosion
Inspect the visible wiring along the left pillars and roof rail for chafing, pinching or previous repairs
Check connector terminal tension and fit, and look for water ingress
Using the manufacturer's procedure, check circuit resistance and continuity with approved test equipment; never probe or measure the airbag igniter directly with an ordinary meter
Clear the code after repair, then cycle the ignition and confirm it does not return

How to fix

Repair or replace damaged wiring sections and secure them away from sharp edges
Clean, re-seat or replace damaged connectors and terminals in line with the manufacturer's procedure
Replace the left curtain airbag module if testing shows it is faulty, using the correct part for the vehicle
Correct any incorrectly routed or trapped wiring after trim or headlining work
Replace or repair the restraint control module only after the wiring and airbag have been proven good, with any coding or setup the model requires

Can I keep driving?

High severity

The car may still drive normally, but the left curtain airbag may not deploy in a crash, which is a safety risk. Limit driving and have it repaired promptly by someone qualified to work on airbag systems.

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