From 2005 onwards, all Volvo models are made safer with an SAS (airbag) system covering both the driver and front passenger. The system has two parts: the Restraints Control Module (ACM) recognizes crashes, while sensors in the B-pillars record side-impact collisions. The airbag network has a safety device attached to each front seat belt, and pyrotechnics launch the steering wheel airbag and passenger-side dashboard airbag during strong impacts. The driver's airbag inflator sits inside the steering wheel, ready to open upon electrical command, while the passenger's larger airbag comes from above the glove box and hangs from a metal base. Side impact airbags install on the outer wall of each front seat's back frame and come out when the vehicle strikes from the side. When the car turns on, the Restraints Control Module provides power to the airbags to ensure they work, and shows the car's "SRS" light to tell you everything is fine. Leave the repair area safe for working on SRS parts by switching everything at the belt off, shutting the ignition, and pulling the RCM fuse. First, leave the engine off and confirm the airbag warning signal is working. Then unplug the negative battery cable, keep the engine off, and wait a full minute before beginning work. Repowering means putting everything back into place: the RCM fuse, reconnecting the battery, and watching to see if the airbag warning light works like it should. When working with an airbag module, always face the airbag opening away from your body and stay clear of testing electrical devices with SRS parts. Only do electrical welding after you detach airbag electrical connections. Also, never throw away airbag modules or seat belt tensioners in the wrong way. Two different steps must be followed to take out and put back the driver's airbag module and clockspring. To work on the passenger airbag module, you need to first disable the whole system, unhook the glove box, disconnect the power cable, then gently separate the airbag from its place behind the dashboard. In the reversal of removal work, bolts must be tightened again, and you need to reconnect the battery. Then, following remediating any trouble codes, the Powertrain Control Module has to relearn how to adjust idle and fuel mix settings to get the best engine running. If you need help with a side-impact airbag module, have a certified garage look at it.
