Central Locks acting strange after replacing passenger microswitch on '87 911

[iwhelan]

Update: the switch I installed must have been defective. I've since exchanged the part with Pelican and the new one works perfectly.

Hi everyone, I've read a ton of threads but haven't found any great info about this.

My '87's central locking system was originally in a state where the driver's side door would lock/unlock with the key, and would operate the passenger door as it should. The only issue was that the passenger door would not lock the system with the key. It would unlock though.

Also, my central lock button on the console only seems to lock, but not unlock the system. I don't know if this is a problem or if it is relevant. (update: this is normal with the car off)

Anyway, I connected the new microswitch and if I move the switch by hand either way, it functions as it should (not connected to door handle). If I put it into the door handle and turn the key counter clockwise, it locks. Turn it the other way, it unlocks, but sometimes relocks as the key springs back to center. There's nothing interfering with the interface of the microswitch with the white plastic bit inside the door handle with the notch that is supposed to activate the switch. I thought maybe it was getting a bit of friction as it returned and going too far, so I even put a little bit of white lithium grease on, without any effect.

If I pull the cam piece off of the door handle so that the lock is no longer sprung, and turn it left and right, it works perfectly. Put the cam and spring back on, and the problem returns. If I turn it slowly and don't let it spring back, it seems to unlock ok most of the time. Keep in mind this is without putting the door handle back on yet.

So, I tried checking everything and there is no adjustment of how the microswitch interfaces with anything so I figure there's nothing I can do, and the only conclusion I can come up with is that the newer microswitch is somehow a lot more sensitive than the original.

I reinstall the door handle, and there's another strange thing going on. When you unlock the passenger side door, you are activating the microswitch, and also the cam on the door handle is pressing the lever that mechanically unlocks the door. Both of these things unlock the system on their own, like when you manually unlock the passenger side door, it unlocks the driver's side door.

What is happening is that I turn the key to unlock and the lock wants to re-lock unless I hold it for a beat and then the central locking system accepts that I'm trying to unlock and then doesn't fight back, and also unlocks the drivers door lock.

So basically I have a mostly functioning system, which I can lock and unlock with the key in the passenger door, but it is quirky, and I have to unlock and hold for a second to get it to unlock properly.

I also tried adjusting the cam on the end of the lock tumbler on the door handle, as this has some adjustability with how it interfaces with the lever inside the door, but it didn't seem to make a difference.

I'm not sure if there are two problems here, first the new microswitch being overly sensitive, and second a lack of sync with the central locking computer as you unlock with the microswitch and the internal lever at the same time.

Any thoughts?

Thanks!

[shadowjack1]

On the lock unlock central lock button, it only unlocks if the key is in the on position. It will lock with the key off but not unlock.
I know that this does not answer all your questions, but its all I have.

[iwhelan]

Thanks, that is helpful. I appreciate it!

[iwhelan]

One detail I forgot to add: Upon inspection of the new micro switch, I noticed that there was a small tear in the clear rubber that surrounds the blue switch itself. I am certain that I didn't cause this tear, and it is hardly noticeable unless you look very close. I am not sure if this rubber is integral to returning the switch to center. I was going to just let it go, but I wonder if it could be a problem, so I have sent a message to Pelican support about a possible part exchange.

update: I have contacted Pelican support and they have offered me the option of exchanging the part, so I will give that a try. I'm not sure if that little tear in the rubber surround was somehow affecting the microswitch, but it could be possible since I'm not able to see what's happening once it is installed. I'll update the thread if anything changes.

[iwhelan]

I am happy to report that Pelican exchanged my microswitch and I've just installed the new one and it works perfectly. I don't know what was going on, but obviously something was wrong with the first switch they sent.