1997 Boxster key doorlocks misbehaving- Suggestions to Diagnose?
 

The door lock mechanism intermittently does not lock.
1) Sometimes, pushing the button on the key fob locks the doors, flashes parking lights - all OK
2) Sometimes pressing the lock button on the key fob causes the locks to close, flashes parking lights, then the locks pop open, horn beeps
3) when 2 occurs, inserting the key into the drivers side door lock and turning the key quickly 2 times
*sometimes* locks the doors and *sometimes* not.

I am looking for some advice on where to start looking and some things to try to fix the problem. Is there a sticky on this site the provides some guidance? - have not been able to locate it.
I came across some postings in the forum that talk about replacing the door locks with volkswagon p/n...how can I determine what door is causing the issue?
TIA
j

I had a similar issue on mine, potentially the same problem. There is a microswitch in the door latch which senses when the door is closed. This switch failed on both sides. If the system thinks the door is not closed it is impossible to lock the car. First you can lock it after the second or third attempt but eventually you won't be able to lock it at all. Replacing the microswitches wasn't sufficient in my case because the failing tab on the switch scored a groove on the rotating cylinder withing the latch that operates it. So I replaced both latches. I went with a cheap Chinese aftermarket latch, it's been perfectly fine so far and no adjustment was needed.

Oh, and to determine which side is failing: try open and close the door on either side and watch if the window drops and remained drop each time.

Where did you source these ???

rock auto only has the one side with the alarm .. looking for the other side

thanks

Got this:
https://www.amazon.com/dp/B0CJ2LJ6V1?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

I’m having an issue with locking doors on my 99 Boxster. I just paid $2400 for a new immobilizer along with key programming.

The key fob (new battery) will not lock or unlock the doors, I started using the key in door to lock. Today. I noticed that the passenger side does not lock. Key fob also not working on rear trunk.

I have scoured my owners manual but nothing there about this particular issue. Help

i thought i needed rev C although im not sure the difference .. was this a 9 pin connector by chance ?

Make shure that you get a door lock that fits your car specs.

The chinese crap will not work with every passenger door.

As i always like to add a little to make the forum better with every problem ..

Issue turned out to be worn plastic coating on the cam actuator for door open/closed switch .

The plastic wears off over time and the metal then wears out the switch. The cam actuator is enclosed in a riveted package so not worth fixing, but it is a VW part so likely could be sourced and just put on the Porsche electronic piece ( easy )

after removing the switch you can see the worn out cam actuator..

https://i.imgur.com/twbYUy8.jpg

So then i took it all apart so people can see all the switches.

https://i.imgur.com/1AUyi19.jpg

There is a microswitch for the key assembly to lock and unlock the door in the top right corner, there is also a small switch to tell the car it is actually locked ( its by the white block on the screw assembly) , and there is the bigger switch that was on the cam ( the one on the wires )

https://i.imgur.com/THKYNNR.jpg

better pic with board removed.
you could solder in new switches if availability or money were an issue , but you would need above mechanical piece too.. This was from a 9 pin assembly if anyone is wondering.