I just replaced my driver's buckle. The switch inside it failed and it intermittently set off the seat belt light, but not the air bag light. It's a 20 minute job and all you need is a couple of sockets. Disconnect the battery first, let it sit for about 10 minutes to disable the airbag residual charge, then unbolt the seat using a triple-square bit and tip it to the left so you can remove the old buckle. There are other connections under the seat, but when you tip it to the side (vice removing the seat altogether) you don't have to disconnect anything except the bad buckle. But be careful that you don't stretch the other connections or break them. Part number is 1K3857755AKYLZ for my '11 GTI. You can get them on-line for about $80.