I changed the hub ring out and it solved my intermittent SRS light. I took the steering wheel out a couple of times and cleaned the hub and the light went out for awhile but came back.

It is an expensive part and it may or may not be the cause. I first bought new brushes (cheap) but they did not solve the problem.

Other causes that I have read about are crap in your seat belt buckle and failing alternator.

Two difficulties, 1) a little nerve wracking working around the air bag and 2) getting the steering wheel off. Other than that just a routine take apart, replace and put back together.