[Dark Skies]

I've had exactly the same problem myself. The problem seems to be, as mentioned above, with the tiny connections that the relay plug into within the motor itself. I think it was AF Juvat or SoCal that informed me that the relay is supposed to be covered with a little rubber boot. Mine was / is missing. I believe that the boot probably holds the relay in place that little bit more snug. Also, of course, it helps keep the **** out of the connections. I tried to buy a new one on its own but was told it was unavailable for the early motor.

Anyway ... I found that the headlights would pop up (switch on) if I slammed the door, drove over a pothole, slapped the wing, slammed the bonnet, kicked a tyre ...

I removed the rubber boot off the motor body and had a good look around at the soldered joints but couldn't see any fractures, dry joints or anything loose causing shorts. Disappointed I reassembled the lot and replaced it on the car.

In the end I got a dental descaler (like a tiny hockey stick for cleaning crap out from under the gumline of yer gob) and pared it down even smaller with a file until I could get it right down in the connections to give it a bloody good clean. Then I took a tiny (tiny tiny) screwdriver and lightly pinched down on the ledges of each female connection slot so they'd grip tighter on the blades of the relay. Finally I got a large rubber o ring - off a plumbing fitting and strapped the relay in tight against the motor. Don't forget to disconnect the battery whilst fiddling with the connections.

Instantly fixed!