B0021 — Left Curtain Deployment Control 1

What Does B0021 Mean?

B0021 is a diagnostic trouble code indicating: Left Curtain Deployment Control 1. This code relates to the body electrical system. It has been reported in NHTSA complaints across 3 different vehicle models.

Symptoms of B0021

⚠️ Airbag warning light on

Common Causes

🔍 Wiring or connector problem

B0021 Reports by Year

2017

1

2019

1

2020

1

2016

1

Real Owner Reports

From NHTSA complaint database — actual owner descriptions.

"WARNING LIGHT: PASSENGER SEATSIDE AIRBAG DEPLOYMENT LOOP CODE: B0021 CAR DEALERSHIP SAID THEY CONTANCED MANUFACTUARE AND SAID THEY WOULD NOT FIX THAT OR WHERE I SUSPECT THE CAR IS HAVING TRANSMISSION PROBLEMS SINCE IT TAKES LONGER THAN IT SHOULD WHEN I ACCELERATE FROM WHERE I START DRIVING AFTER "
— Chevrolet Traverse owner, 06/12/2019

"CAR HAS HAD SERVICE AIR BAG LIGHT ON FOR YEARS PRIOR TO BEING INHERITED. 4 CODES WERE PULLED INLCUDING: 1. B0021 PASSENGER SEAT SIDE AIR BAG DEPLOYMENT LOOP OPEN. 2. B001B PASSENGER PRETENSIONER DEPLOYMENT LOOP 2 OPEN. 3. B001B PASSENGER PRETENSIONER DEPLOYMENT LOOP 2 HIGH RESISTANCE 4. B001B PA"
— Chevrolet Impala owner, 11/07/2020

"I TOOK MY CAR TO AUTO MALL IN BRATTLEBORO VT FOR THE RECALL 36110 PASSENGER SEAT OCCUPANT SENSING. THEY HAD IT ALL DAY SAID THEY FIXED IT BUT THE AIRBAG LIGHT IS ON AND IT STILL DOESN'T SENSE ANYONE IN THE PASSENGER SIDE SEAT. THEY ALSO GAVE ME A LIST OF 9 CODES THAT MY CAR NOW HAS BUT DIDN'T BACK"
— Chevrolet Impala owner, 08/17/2016

Source: NHTSA Complaints Database

Most Reported Vehicles for B0021

Based on NHTSA owner complaint data.

#	Vehicle	Reports
1	CHEVROLET IMPALA
2	CHEVROLET MALIBU
3	CHEVROLET TRAVERSE

B0021 Reports by Vehicle

Detailed NHTSA complaint analysis for each vehicle model.

CHEVROLET IMPALA

2 NHTSA reports · Peak: 2009

Frequently Asked Questions

Can I drive with this code?

It depends on the severity. If the vehicle runs normally, short trips are usually OK. If you notice performance issues, drivability problems, or warning lights beyond the check engine light, get it checked soon.

Will this code clear itself?

Some codes clear automatically after the underlying issue is fixed and several drive cycles pass. But the root cause must be addressed first.

How do I find the exact cause?

A code alone doesn't pinpoint the failed part. You need a diagnostic scan ($50-150 at most shops) that reads freeze frame data and live sensor readings to identify the specific component.

What To Do Next

Possible Fixes

🔧 Have the code scanned with a professional-grade scanner to read freeze frame data
🔧 Inspect wiring harness and connectors for damage, corrosion, or loose connections
🔧 If DIY repair isn't feasible, get a diagnostic from a trusted mechanic ($50-150)

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

B0021: Left Curtain Deployment Control 1