Hi,
I had to remove the air-bag and steering wheel to get to the faulty horn connector and, when I put it all back the SRS light was on. I'm sure you all know more about this than me but it took me some time, and a scan through the Volvo groups, to find information about the "A" and "B" connector blocks by the screen wash filler (under the bonnet).
My comment for others in the same situation is that when you press the button on the "A" block what you get depends on how long you press it for....
A 1 second press results in the LED on the "A" block pulsing out the error code - in my case 2-1-2.
It seemed that if you pressed the button for slightly longer than 1 second - but not quite 5 seconds - nothing happens.
If you press it for 5 seconds, nothing happens for 3 seconds whereupon the LED on the "A" block then comes on. If you press the button again (whilst the LED is on) and hold it for more than 5 seconds the fault log in the ECU is reset and the SRS light goes out.
If you press the button for longet than 5 seconds then nothing happens.
My reason for posting this message is that if you are unsure what you are doing when you're trying to reset the SRS light then take your time
- it is easy to get freaked out pressing the bloody button and watching the LED but it does work - trust me.