B0022 Code: Left Curtain Deployment Control 2
Fault in the second firing loop of the left roof-rail curtain airbag; GM and others use B0022 differently.
Unverified: this manufacturer-specific definition comes from a single source or varies by model. Confirm it with a brand-specific scan tool.
Stop driving
Drivable, but the left-side head protection may not deploy in a side impact or rollover. Don't pull pillar trims or the headliner loose yourself and get the loop repaired soon.
Safety first · Consult a professional
- Airbag (SRS) circuits must only be serviced by a professional. Never probe airbag connectors — accidental deployment causes serious injury.
At a glance
Severity: High
- Meaning
- Left Curtain Deployment Control 2
- System
- Body Systems · Body
- Safe to drive?
- With caution
- Typical repair cost
- $100–$1,800
- DIY difficulty
- Professional only
Curtain airbags run along the roof rail above the side windows and drop down to cover the glass in a side impact or rollover. Their inflator and connector usually sit behind the headliner or a pillar trim, often near the rear pillar. SAE J2012 defines B0022 as the left curtain's deployment control 2 loop: vehicles with a second curtain inflator, a longer curtain for a third row, or a separate rollover stage use this second circuit. The code sets when the airbag module measures that loop open, shorted or out of its resistance range. GM applies its own numbering to B0022 on many models (for example a frontal or pretensioner loop), so the definition varies by make and this page is marked unverified. Typical real-world triggers are headliner removal, roof leaks and aftermarket wiring routed behind the pillar trims.
How to read B0022
- B Body
- 0 Generic (SAE)
- 0 Body Systems
- 22 Specific fault
Symptoms
- Airbag warning light stays on
- Light appeared after a dashcam, radar detector or antenna cable was tucked behind the A-pillar or headliner
- Code after sunroof, headliner, roof rack or grab handle work
- Water stains on the headliner or damp pillar trims (blocked sunroof drain, leaking roof rail)
- Often only loop 2 is flagged while the first curtain loop (B0021 in SAE numbering) is fine
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Curtain airbag connector behind the headliner or pillar trim disturbed during interior or roof work
- Water from a blocked sunroof drain or leaking roof rail corroding the connector
- Aftermarket wiring (dashcam, antenna, roof accessories) pinching or tapping the curtain harness
- Curtain airbag inflator for loop 2 out of range
- Make-specific definition (GM) pointing to a different airbag or pretensioner loop
- Airbag control module fault
Diagnosis step by step
Read the code with make-specific text
Use a scan tool that shows the airbag module's own description and subtype. If it says left curtain loop 2, follow the roof path below; on GM vehicles the tool may name a completely different circuit.
Tools: OBD-II scanner
List any roof or pillar work
Note dashcam or GPS cable installs, roof rack mounting, sunroof drain cleaning, headliner replacement or grab handle removal. Those jobs expose the curtain harness and its plugs.
Look for water inside the roof line
Check the headliner and pillar trims for stains and feel the carpet under the pillars for dampness. Blocked sunroof drains often empty into the pillar where the curtain connector sits.
Tools: Flashlight
Don't route cables across the curtain path
If you installed a dashcam, don't pull the trim again to fix it yourself. Cables or clips across the curtain's fold line can also obstruct deployment, so the shop should reroute them while the SRS is disabled.
Shop repair of the curtain loop
The technician disconnects the battery, waits out the reserve energy time and lowers the trim to reach the connector. A simulator shows whether the curtain inflator or the wiring is at fault; corroded plugs are replaced with SRS repair parts.
Tools: OBD-II scanner
Fix the leak and confirm
Any roof leak is fixed before the trim goes back. After clearing the code, the SRS light must go out and stay out after a wet-weather drive.
Tools: OBD-II scanner
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| SRS diagnosis | No | $100–$200 |
| Repair curtain airbag connector behind trim | No | $150–$400 |
| Clear sunroof drains and fix roof leak | No | $100–$400 |
| Replace left curtain airbag (headliner removal) | No | $700–$1,800 |
| Replace airbag control module | No | $500–$1,300 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Notes by brand
Chevrolet
On many Chevrolet models B0022 is a GM-specific code for a frontal airbag or seatbelt pretensioner deployment loop, not the left curtain. Check the exact description with a GM-capable scan tool before any parts are ordered.
Field data
| Chevrolet | 5 | ||
|---|---|---|---|
| GMC | 3 | Acadia, Acadia Denali, Yukon Xl 2500 |
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.
Emissions / smog test impact
Depends
Not part of the US emissions test. States with a safety inspection can reject a vehicle while the airbag warning light is on.
Frequently asked questions
What does 'deployment control 2' mean for a curtain airbag?
It's the second firing circuit for the left curtain. Vehicles with two curtain inflators, extra-long curtains for a third row or a separate rollover function use it; the first loop is reported with its own code.
Could my dashcam installation have caused B0022?
It can, if the trim was pried off and the curtain plug was disturbed, or if the cable pinches the harness. The cable must also stay clear of the curtain's fold line so it doesn't block deployment.
Why would a sunroof leak set an airbag code?
Sunroof drains run down the pillars, right past the curtain airbag connectors. A blocked or split drain soaks those plugs, and corrosion changes the loop resistance.
Is B0022 the same on every car?
No. SAE lists it as left curtain loop 2, but GM and some others assign the number to other circuits. Always read the manufacturer's text for your vehicle first.
Sources
- SAE J2012 – Diagnostic Trouble Code Definitions
- Manufacturer public service information (cross-checked)
- NHTSA Complaints API
- Methodology: How We Build Code Pages · Data Sources We Use · Editorial Policy