VOLVO
SRS-B00021B - Driver Frontal Stage 2 Deployment Control. General Electrical Failures. Circuit resistance above threshold
System
Supplemental Restraint System (SRS)
Volvo models this fault code applies to
Applies to the following models:
9 modelsS60 (2011–), S80 (2007–), V40 (2013–), V40 Cross Country (2013–), V60 (2011–), V60 Cross Country (2015–), V70 (2008–), XC60 (2009–), XC70 (2008–)
What does this fault code mean?
The SRS measures resistance in the stage 2 driver airbag circuit. If the resistance stays above the limit for too long, the code is stored. The fault is an open circuit in the wire, the connections, the airbag or the clockspring.
Possible causes
- Break in the wire
- Contact resistance or oxidation at the connections
- Open circuit in the stage 2 driver airbag, where the igniter section has too high a resistance
- Open circuit in the clockspring
What you can do
- 1Read and clear the code, test drive to see whether it comes back
- 2Have a workshop check the connectors and the wire between the SRS module and the stage 2 airbag for breaks and contact resistance
- 3If the wire is intact, have a workshop replace the stage 2 driver airbag
- 4Do not handle the airbag system yourself; leave it to a workshop
Symptoms you may notice3
- SRS warning lamp on
- SRS warning message shown
- Warning symbol and text message in the display
General guidance for car owners. Diagnosis on the car can point to a different cause.