There is a little switch in the rear door handle that releases the glass which sometimes fails. Basically the wires come off the switch inside that require soldering back on. Switch is in the door handle that needs taking off the door to fix (see bottom picture)

If you look at his picture here, this is what a broken switch looks like removed from the door handle

You can see the contacts the wires have broken off, I just removed the top rubber cover, cleaned & resoldered the wires & replaced the rubber cover by covering the wires in glue from a hot glue gun

There is a slight mistake on that picture as I didn’t set the wires coming out at 90deg to the switch so I had to cut away at it to reposition the wires.
:banghead:

I didn’t bother with the metal clip when refitting the switch, just glued it in, hopefully the glue will stop the moisture getting in the switch. If it fails again it is easy enough to cut the switch out, the glue isn’t that strong.