It's actually 4 crimp connectors which need to be removed/replaced or wires soldered (my choice). The fusebox is literally unscrewed and pulled up as that's the only way to access those connectors and all relays under the dash are also removed to do that. It was a campaign years ago and unless you know exactly which 4 wires with crimp connectors you're looking for, I doubt that you'll find them w/o a good picture. It's because of that, plus the need to use Volvos VST to read/erase the codes that I wouldn't advise you try it youself. I'd suggest paying the local dealer.