Doors Unlock Spontaneously

Doors Unlock Spontaneously

OK, what causes my 88 S4's door locks to close and then re-open of their own volition 1 second later. The rear deck is securely closed, as are both doors. Same thing when the car is off, or while the motor is running and I push the dash button.

Ideas, ye of greater knowledge?

Don Davis

I learned this from C.C. White, I think. There are a pair of tiny inline fuses behind the fuse panel. In my experience one or both of these has given up the ghost. They a .4 amps. I got .5 from Radio Shack.

Kevin Berez (kaberez@mindspring.com)
'86.5 928S Auto Meteormetallic

Add my vote that it is definitely one of the inline fuses. This happened to me personally.

David Schaum
86.5 928S Auto/Iris Blue Metallic
Tag "CHK YR 6"

In addition to the fuse panel fuse (#21 on my car) , the two small in-line fuses for the door locks are behind the fuse/relay panel. There simply wasn't room for Porsche to fit them all on the panel itself. Look for black wires with red or blue piping. It's not hard to get it there by undoing the 2 10mm self-tappers that hold the whole panel in place, but probably a good idea to disconnect your battery first as you don't want to earth out the mass of wiring you'll be holding in your sweaty palms.

The fuses are special ones - slow blow ones with their own special Porsche part # (and price, probably.) People often substitute commonly available fuses - I cannot comment on this practice, other than it will have less impact on your resale than fitting a Chev, and will probably go unnoticed at most concourses d'elegance.

'84 928

I had the same problem on my 84 928s. I found it to be the motor mechanism in the door. It is adjustable foward and aft. If its out of adj. my locks would cycle. Removed the door side panel, arm rest etc. and it is
located right behind where the lock is. The tolerance band is small so only minor adjustments are necessary.

Good luck,

Turns out that the problem turned out to be the plunger switches in the passenger door jamb, as more than one person had suggested. Tweaked it a bit, and that stopped it. I haven't gotten to actually pulling it out and cleaning it right yet, but it's on the list. Evidently it was still sensing an "open" door, and caused the locks so cycle back to open.

Thanks to all for the expert advice, as always. Whether we know it or not, what we've got through the lists is something like a virtual garage, with more expertise than most people think!

Ciao - dd
Don Davis

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