I replaced the window regulator on the passenger door (2004 Fabia). But when removing the door carrier I couldn’t release the connector for the door lock mechanism. In the end I resorted to cutting the wires to the door lock. I have reattached everything, including riveting the carrier in place. I have reconnected the wires to the door lock. The window mechanism works fine, but now the door lock doesn’t operate. The three other doors lock and unlock but the passenger door doesn’t. I can hear a tiny continuous electrical hum or buzz coming from the door lock mechanism. Have I damaged the door lock electrics when I cut the wires? Or does it need resetting somehow? Or is it just coincidence and the door lock mechanism needed replacing anyhow? I just wanted to check if anyone had any ideas before I order a new lock mechanism. I also don't want to have to drill out all the rivets again if I don't have to...

Coincidence, the lock needs replacing.

Have you definitely joined the right wires back up again after you cut them?

The door lock module contains nothing but a motor, some microswitches and some resistors, as far as I recall, so unlikely to have been damaged by your cutting.

The hum/buzz you're hearing must be the motor trying to run, so as Lee says, make sure connections aren't crossed over somehow, and nothing is shorting to chassis metalwork.

I must admit that I made a basic assumption of competence on the part of the OP that they'd be able to correctly splice colour coded conductors back together having had the confidence to cut through the loom in the first place.

I guess if they're not soldered and heat shrunk then the connection may not be good enough to pass the current the locking motor needs.

One of the worst jobs I’ve ever done ( was an Hgv fitter) replacing the window regulator. There’s got to be a knack to doing it.

broke the clip for the pop up chrome button getting it to bits and ended up throwing it away trying to get it back together.

And as for it being held on with rivets arghhh, ended having to go to a Hgv garage to use heavy duty panel rivets.

i had issues with it not locking but it was because I was struggling to get the connection back on the lock 

A absolute pain in the rear