Code result
B0021
Left Side Deployment Stage 1 Control
Moderate severity
What it means
The SRS module has detected a fault in the deployment control circuit for the left side (driver) airbag stage 1. Side impact protection on the driver side may be reduced.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Loose airbag connector under driver seat
highOne of the most commonly reported causes for this code — check this first.
Wiring pinched in seat rail
mediumA plausible cause — test and verify before replacing parts.
Side airbag module internal fault
lowLess common, but worth ruling out after the more likely causes.
Related help
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