Can't lock door from outside - please advise

polizei · 05-06-2008, 07:51 PM

I finally got some time to chase down my locking problem on my '87 911. When I try to lock the door from the outside (when shut), the key turns but does not lock the door; however, if the door is locked, the key will unlock the door. I think the problem resides with the key mechanism and not the door latch. It seems that there is something missing from the key mechanism.

Here's a picture of the key mechanism and the door latch in the normal position (door closed):

Here's a picture of locking with the key:

Here's a picture of unlocking with the key:

Here's an up close of the key mechanism:

Please help!

vreference · 05-06-2008, 08:20 PM

Microswitch problem (or central locking?). This missing ear to mechanically lock the door is normal, My '89 has the same setup.

PSportoVeloce · 05-06-2008, 08:43 PM

i have the same problem but i can't unlock the door from the exterior with the key, i took my door panel apart and found that the little guy with the grey condom looking thing on it would not touch the pin that was actuated by turning the key. when i actuated it myself then the door would unlock. it seems to be a mechanical problem in my case (something bent perhaps?)

DRACO A5OG · DRACO A5OG's Garage

Check the white wire, mine was cut and shorted every time I tried to use the key. I moved it and taped it up. Problem solved for me

my 2 cents

polizei · 04:11 AM

Quote:

Originally Posted by DRACO A5OG

Check the white wire, mine was cut and shorted every time I tried to use the key. I moved it and taped it up. Problem solved for me

my 2 cents

The white wire is for the alarm system, right? I don't think this is the problem as its physically impossible for the key mechanism to touch the door latch while the door is unlocked. Your comment got me thinking, however, that maybe the key mechanism is different for cars that have the alarm versus those without. Perhaps Porsche assumed you would lock your car only through remote control. Does anyone without an alarm system have a similar picture to the above key mechanism/door latch?

polizei · 05-07-2008, 08:07 AM

Quote:

Originally Posted by vreference

Microswitch problem (or central locking?). This missing ear to mechanically lock the door is normal, My '89 has the same setup.

Please excuse my ignorance, but what is the microswitch exactly? The reason I don't think it's a central locking system (cls) problem is that the cls locks the mechanism via an operating shaft farther down the latch mechanism. It's #6 below:

Notice how the top piece of #1 (latch mechanism) has two ears instead of one, like mine has. If mine had that 2nd ear, problem solved. But as I look at it, it appears that it was designed to have one ear and that it's sustained no damage.

More thoughts?

rnln · 05-07-2008, 08:32 AM

I have this problem on locking one door. I have not taken it apart yet, but have a trick to treat it. Every it happend, and it happen most of the time I use key, I pull the trigger while turning the key. Work every time.

ossiblue · 08:54 AM

Here are my thoughts, since you did ask (BTW, I have no first hand knowledge, don't have electric locks, but I'm interested in unsolved problems. Take the following for what it's worth...)

I think the microswitch (if it exists) referred to is somewhere in the system identified by the #4 in the diagram--activated by turning the key in the lock. Since none of the parts are identified in the diagram, it's hard to describe what's going on but maybe the object at the other end of the cable from #4 is activated by the key cylinder and the servo (#5) responds by locking/unlocking the latch mechanism (#1). The "ear" on your lock mechanism is only needed for a default to unlock the car if there is a failure of the electronics, as it would ordinarily work by the servo. I suspect there is something in or around the key cylinder (microswitch?) that is at fault.

Anyway, those are my uneducated thoughts. I don't think your mechanical parts are bad, but something is amiss with the electronics--possibly a connection, broken wire, or microswitch.

BTW, does the problem exist with both doors?

polizei · 05-07-2008, 09:35 AM

Quote:

Originally Posted by ossiblue

Here are my thoughts, since you did ask (BTW, I have no first hand knowledge, don't have electric locks, but I'm interested in unsolved problems. Take the following for what it's worth...)

I think the microswitch (if it exists) referred to is somewhere in the system identified by the #4 in the diagram--activated by turning the key in the lock. Since none of the parts are identified in the diagram, it's hard to describe what's going on but maybe the object at the other end of the cable from #4 is activated by the key cylinder and the servo (#5) responds by locking/unlocking the latch mechanism (#1). The "ear" on your lock mechanism is only needed for a default to unlock the car if there is a failure of the electronics, as it would ordinarily work by the servo. I suspect there is something in or around the key cylinder (microswitch?) that is at fault.

Anyway, those are my uneducated thoughts. I don't think your mechanical parts are bad, but something is amiss with the electronics--possibly a connection, broken wire, or microswitch.

BTW, does the problem exist with both doors?

This makes PERFECT sense! Thanks for taking the time to explain

In fact, I think the problem may already be resolved!

To answer your question, yes, the passenger side door does lock correctly. I went to take a look at the passenger lock mechanism to see if it was the same as the driver's, and it indeed it was. I was baffled as to why the passenger-side door wouldn't lock when I tried it the other night, until reading your post. I've had the battery cables disconnected all this time because I'm going through a rebuild & turbo project currently. So, all the while, I've been trying to fix a problem that can't be properly diagnosed! *Whacks forehead* Not all is lost thought, as I had to replace operating rod #6 since the driver's side door wouldn't lock when the central locking system button was pressed. If the microswitch is not at fault, the new operating rod should have fixed the problem . I guess I'll just have to connect the battery and find out.

Thank you so much for your help!

ossiblue · 05-07-2008, 10:09 AM

Glad my shot in the dark could help, Andy. I learned as much about this system as did you by following your posts--a learning experience for me.

ccus944 · ccus944's Garage

polizei,
Did you ever get a resolution to your problem?...I found this because mine is doing the exact same thing...If I lock my doors...either with the remote, or using a key in the passenger door...I can unlock it with the key in my driver door...but I cannot lock it with my key in the driver door...I did remove the door handle/disconnect the white wire to repair the trigger...looking for a fix...Thanks, CC

MechanicalBird · 07-03-2021, 04:51 AM

Ossiblue & polizei - Thank you so much for helping to complete a 2 month project initiated by a broken exterior door handle trigger.

I had the exact same experience as polizei but when I plugged in my battery and the door handle cable, the key still did not lock the door. So, I cleaned the locking mechanism and put some dialectic grease on the microswitch and bam!

The way the microswitch functions is kinda cool. I uploaded a related video:

https://youtu.be/l1ggyVsVUpA (1986 Porsche 911 - Door Locking Mechanism on Exterior Handle)