I'd be VERY surprised to find out it's anything wrong with the power lock relays. They're tough and the circuit is really simple.

The part of the system that wears out is the wiring in the door hinges, and the switches themselves- specifically the one that's like a ring around the door lock cylinder.

Simple and easy to remove, if you're looking at an opened-up 240 door. The switch in the driver's door lock-rod and the switch wrapped around the lock cylinder, are wired together to the three wires coming through the door hinge and to the relays.

If you want to verify that it's in the driver's door, do this: over the driver's left knee, roughly under the headlight switch, from under the dash locate the plug for the locks. It's a three pin plug, the end of it looks like this : [ O O O >

There's a black wire, a red wire, and a green wire. Nothing else. Unplug it, have her drive the car for a day (and lock the car manually!) The gremlins will be gone, I'm sure of it.

Now you have to figure out if it's chewed up wires in the door wiring duct or if it's at the switches. A similar connector exists inside the door, so the switches can be isolated and the hinge wiring only can be tested.

Note that the locks activate by connecting the red (unlock) or green (lock) wires to ground (the black wire)... of course they activate as well if the wire is cut or crunched in the door hinge area and touching sheet metal somewhere.

I just fixed these wires for my neighbor's 88, and a friend just told me his 84 is now unlocking all the time, draining the battery. It's one of those things that can just wear out due to old age.
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::: Rob Bareiss, New London CT ::: 92 244 M47 211K ::: 90 745GL M47 273K ::: 88 245DL AW70 190K ::: 84 242DL Project ::: 70 VW Bus ::: 70 VW Pickup Project ::: 71 VW Notchback :::