First look for a bad wire and you do not even need to remove the door
panels.  Look at the pressure point where the door hinge meets the body
after years of repeated opening and closing of the door the wires become
weak and break.
Find the bundle of wires which run into the door at the hinge location.  The
wires are usually all contained in a rubber sleeve, make a small incision in
the sleeve and find the cracked or broken wire. Fix the wire and then
reinforce the location with a short piece of welding rod to prevent future
troubles.  It was a 30 min job max.
Marcus

91 carat
86 gl