Strange behavior of door locks

[boxster_nut]

Hello:

1997 Boxster, all stock, 32K miles.

All doors closed, top up & locked, hood and trunk closed tight.  Hit the key lock on the key FOB.  All locks go to lock position, 2-3 second later, door locks pop open.

Tried same configuration with manual key-turn to lock, all locks go to locked position, 2-3 seconds later door lock pop open. 

I checked the microswitches in windshield frame for convertible top - behaves normally.  Door windows appear to work normally.

I changed driver’s side window regulator about a year ago, reset limits and everything worked fine.

What could possibly be the problem??

Guidance to start troubleshooting this is appreciated.

Best regards,

J

 

[Richard Hamilton]

It sounds like a microswitch within one of the door locks which senses if the door is open or closed is broken.  The system 'thinks' the door is open, so after locking it immediately unlocks.

As a temporary measure, you can use the emergency locking procedure.  Turn the key in the door lock to the lock position and back 3 times in quick succession.  It may also work if you press the remote button 3 times.

[boxster_nut]

12 hours ago, Richard Hamilton said:

It sounds like a microswitch within one of the door locks which senses if the door is open or closed is broken.  The system 'thinks' the door is open, so after locking it immediately unlocks.

As a temporary measure, you can use the emergency locking procedure.  Turn the key in the door lock to the lock position and back 3 times in quick succession.  It may also work if you press the remote button 3 times.

 

You are spot-on!!! After spending a good amount of time piecing together information from various sites (Porsche, VW (bug, jetta, passat), Audi) I got a good picture of the switches, what they signal, possible replacements, and alternatives.  Unfortunately, the p/n 3B1-837-015-E  for my door latch is NLA from most places - except pelican who's price is $310 (ouch!!).  IF the VW places had them, the posted cost is $100-$115 depending on the merchant.  There are all sorts of p/n variations with suffexs such as AC, C, D and E. I didn't find any source that compared these switches to identify the differences.  My guess is that the micro-switches are common, the mechanical arrangement and the electrical pins on the connector are different.

 

The cost of all the replacement switches won't be more than $25 total.  (I may buy one of the parts that are 'close' with a suffex of AC, or C or D and cannibalize the switches out of it - these cost anywhere from $30-$60 and I am guessing that the switches inside are all the same, just the mechanics are different). In any case, an hour spent to rebuild/retrofit the switches is worth the $300 savings.

 

The tip about turning the key in the door lock to the lock position and back 3 times in quick succession worked like a charm!  Now I can at least drive the car and lock it.

Thank you very, very much.

As I found out, this switch problem is prevalent in 911's as well.  It is ironic that such an expensive vehicle would use parts that are common among 3-4 lines of automobiles with at least 6 different vehicle versions.  Buy a porsche, get volkswagon parts,...or by a volkswagon, get porsche parts....yea, I know, not quite the same.....well, the infamous 914 of the 1970 was basically all volkswagon..but I digress.

J

[Richard Hamilton]

The switch which senses if the door is open or closed is shown in the photo, with red and blue wires running to it:
 

 

I'll wager it looks like this:

 

[boxster_nut]

Do you happen to know p/n?

Thanks

J

 

[Richard Hamilton]

The microswitch itself isn't available from Porsche.  I think it is made by Burgess, but I'm not sure.