BB: Rollover Deployment Record

Stored crash data

What BB means

A rollover triggers a different deployment pattern than a frontal crash. The control unit fires the curtain airbags and the seat belt pretensioners to keep occupants in position while the vehicle is turning over. Code BB documents that the module issued those firing commands, which makes it a record rather than a fault.

Records like this are held in protected memory. Disconnecting the battery leaves them intact, a scan tool clear will not remove them, and the airbag lamp stays on as long as they are stored. That is intentional, because it keeps a vehicle with spent restraints from being passed off as a car with working ones.

Common causes

• A rollover event that fired the curtain airbags and pretensioners
• Curtains and belts already deployed in the vehicle's history
• A used control unit installed from a car that rolled over
• A module returned to service after a repair without the stored record being cleared
• Restraints fired during salvage processing of a rolled vehicle

Crash data or hardware fault?

This is stored crash data, the category where a module reset is the actual repair. Live circuit codes are the other kind, and they behave nothing like this: a circuit code reflects a resistance reading at that moment and disappears the instant the wiring is corrected.

Does our reset clear it?

Once the car is repaired, mailing us the control unit is what clears code BB. Replace the deployed curtain airbags and pretensioners with genuine OEM parts, repair harness damage in the pillars and roof rail, and check the rollover and side sensors. Then pull the module and send it in. Installing it before the restraints are replaced only leaves you with different codes.

Which makes throw it

The rollover firing output carries code BB on Subaru. The definition names curtains and pretensioners together, which is a useful reminder that a rolled car needs new belts as well as new airbags.

What to do next

Build a complete parts list before touching the module, since a rollover fires several restraints at once and the system reports anything missing. Replace the curtains, the pretensioners, and any damaged trim clips and harness sections. Inspect the roof rail wiring where the curtains tore through. With everything in place, ship the control unit to us for reset, and call 501-988-0611 if you need Subaru curtains or seat belts. Related codes: B1801, 11, B11F7.