That's an a-hole move, and I make no apologies about saying so. There is NO excuse for unplugging the light. Besides, what if you smash the car up and the thing doesn't go out. A little investigation uncovers that in a hurry.

The SRS light can be checked with a test lead inserted into the SRS test port, which lies behind the ashtray in the fusebox. It's one of the two sideways ports in the ashtray; the one with one contact in it.

What you have to do is to put the test lead in the test port. Turn the ignition to "on" (don't start the bucket; just turn on the ign).

Wait a moment for it to do it's self test. Then put the test lead that you have plugged in, to a ground. The outer part of the lighter socket is a great spot, but there are other grounds if you're in a jam (or the lighter socket is marginal/disconnected). The SRS light should go out. Again, just a couple of seconds and release it. The light should flash the SRS code it has stored. Usually that's a "5", but not always.

Then to clear the codes out, ground the test lead again three times very quickly, for less than a half second apiece. Just do it 1-2-3 and release.

The SRS light should go out, then come on again, and then go back out. If it stays out, you're OK. Sometimes bad voltage from the battery will cause an SRS light despite lack of other reasons.
--
chris herbst, five volvos.