B0013 is the stage 2 side of the driver frontal deployment loop on GM vehicles. It is its own pair of wires feeding the second charge in the steering wheel airbag, and the SDM tests it separately from stage 1. Seeing B0013 by itself is common, and it narrows the search to one circuit pair instead of the whole column.
A dual stage driver airbag has two inflator charges. The SDM decides during a crash whether to fire only the first, or to add the second either at the same instant or a few milliseconds later, based on crash severity and belt use. Stage 2 has its own initiator, its own terminals in the clock spring, and its own diagnostic loop. That is the loop B0013 reports on.
The symptom byte tells you the fault type. GM lists B0013 01 as short to battery, 02 as short to ground, 04 as open circuit, 0D as resistance above the threshold, and 0E as resistance below it. On GM trucks the descriptor reads Driver Steering Wheel Air Bag Deployment Loop Stage 2.
Because both stages share one clock spring, a coil that has worn through a single ribbon trace can drop stage 2 while stage 1 keeps measuring in range. That is why B0013 shows up alone so often, and why replacing only the airbag rarely helps.
This is a circuit code, not a crash record. It reports what the SDM measured on the stage 2 pair. Keep in mind that a spent stage 2 charge reads as an open circuit forever, so on a vehicle that has been in a collision you will typically find B0013 sitting beside a deployment record. The open loop and the locked module are two different repairs on the same car.
No. Clearing the module's memory does not repair a coil or a connector, and B0013 sets again as soon as the SDM runs its next check. Repair the circuit first. If the vehicle deployed and the module is also locked with crash data, the module goes out for an airbag module reset after the airbag and coil are replaced. Replacement clock springs and driver airbags for GM applications are in the parts store.
B0013 in this form is GM SIR data, seen on Chevrolet, GMC, Buick, Cadillac, Pontiac, and Saturn vehicles from about 2005 through 2014. On earlier Class 2 GM vehicles the stage 2 faults carried different numbers, with B0042 for low resistance, B0043 for voltage out of range, and B0044 for an open stage 2 loop. Some import manufacturers use B0013 for unrelated circuits, so match the code to the module that set it.
Note the symptom byte, then check whether stage 1 is also flagging. If B0012 is stored alongside it, treat the coil as the prime suspect. If only stage 2 is failing, inspect the coil connector and confirm the installed airbag is the correct dual stage part for the VIN, since a mismatched bag is a frequent cause after a repair.
Before buying anything, verify the resistance readings with the connector disconnected and the proper load tool rather than a meter across live squib circuits.
Related codes: B0012, B0026, B0002
Keep reading:
Code scope: Chevrolet, GMC, Cadillac, Buick. The same number can mean something different on another manufacturer, so match the code to your make before you act on it.
A reset clears stored crash data. A replacement part fixes a hardware fault. We have read these codes since the nineties and will tell you which one you are looking at.
Genuine OEM, tested, and shipped ground from Jacksonville, Arkansas.
Chevrolet parts and codes · Do not see it listed? Request a part or call 501-988-0611.