Here is some information that may prove useful when one gets an anti-skid service required warning in the P2 cars.

A couple months ago, I started getting the dreaded "anti-skid service required" warning on my 2007 XC-70. It would come on occasionally while driving, and stay lit until I shut the engine off. Upon start up, it would still be on, then go out after driving a short distance. Depending upon the day, the phase of the moon, temperature of the car, etc.; it would come on again. Scanning the car with my DICE box and VIDA, there were codes from the BCM (Brake Control Module)(icon was red) and other errors coming from the SAS (Steering Angle Sensor). I also noticed that when the indicator was lit, the ABS and AWD was off-line. Not a good thing with winter approaching in upstate NY. After a while, I noticed a pattern. The indicator generally came on when I had to turn right, requiring the steering wheel to be turned 90 degrees or more to the right. With this pattern, I figured the problem was likely associated with the SAS and not the BCM, which gets information from the SAS.

Knowing the local stealership, (which often charges 20% - 30% over list price for parts) was going to screw me again, I ordered a new SAS from one of the online Volvo parts sites that sell genuine Volvo parts at discount. I knew I may still end up taking the car to the stealership to have the new SAS paired with the car. But, at least they could not over charge me for the part. Installing the SAS turned out to be not too bad a job. After disconnecting the battery and letting the car sit for a while, one needs to remove the steering wheel air bag and the steering wheel. There are a number of videos on how to do this. However, the ones I saw dealt with 3 spoke steering wheels. When the screw driver trick used to remove the air bag did not work, a little research showed that there is a different method for those of us with 4 spoke steering wheels. All it takes is a Torx30 driver and a good hard twist to break free the two screws that hold the air bag onto the wheel. The two screws are located in the holes on the back of the main spokes. Once the air bag is free, the replacement is essentially the same as that shown in the video from FCP.

Now comes the question of pairing the SAS with the car. There is conflicting information about whether or not this would be required. Even VIDA suggested I would have to take the car to the stealership. I started the car, indicator light was off, and has stayed off for over a week doing the repair. ABS and AWD seem to be working as well. It looks like either there has been a software update done before I bought the car 1.5 years ago, or later versions of the SAS/BCM do not VIN-lock the SAS. Either way, things are working again and I am ready for snow to finally arrive.

Hope this is helpful.
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Gary D