Simon928

My central locking has never worked since I bought the car, and there have also been some other possibly related gremlins, so I just wanted to ask what your opinions were about the most logical route to go about fixing this issue.

First off, I'll describe how it works (or doesn't work). When I turn the key in the door, it has no effect on the other door, and if I understand correctly when I lock/unlock one door with a key it should do the same to the other.

When I hit the central lock button on the console, the drivers door lock usually cycles constantly--lock and unlock, and if it stops it always stops in the locked position, never unlocked. I just tried it again today and it worked properly, so the cycling seems to be intermittent. The passenger side door seems to exhibit the same behaviour as the driver's door , but I had to disconnect the wavy metal arm with the spring that connects to the power locking mechanism because the passenger door would always automatically lock when it was closed. The spring was too tight and forcing the door to lock because (I'm assuming because it was out of adjustment), but since the central locking wasn't working anyways disconnecting it at least made it work properly in manual mode.

Now to possibly related issues. The following might be completely irrelevant, but I thought I'd bring them up in case they were related to the locking issue.

1) The alarm sometimes goes off when I open either of the doors, but will disarm if I put the key in the lock and turn it. This happens very, very rarely but I thought it might be relevant.

2) My door chime also started going off while I was driving awhile ago (stayed on and couldn't be turned off), but I didn't have the opportunity to troubleshoot at the time so I just pulled the relay under the console.

All of my door switches seem to work fine in the sense that the interior lights (which all work) shut off when the door is closed, but could there be something else in there that could be causing these symptoms? I don't really give a crap about the door chime and the alarm going off intermittently per se, but I thought that I would bring these things up in case they were all related.

Any insights would be appreciated, as I am pretty useless at electrical stuff.

Thanks!

The Forgotten On

First, be sure you have the correct relay. It has 5 large pins ( unlike a 53 relay it has a 87a pin in the center). This relay powers the windows too, it only unlocks when the car is off.

More than likely you will need to remove the door panels and either replace the lock motors if they are broken or (more than likely) adjust them.

There is a procedure for this in the shop manual in section 57-21.

I adjusted mine and they work well now in my 81 as they were way out of adjustment when I adjusted them. It also doesn't hurt to open them up and clean out all of the contact traces.

Simon928

Thanks for the info, that's really helpful! I wasn't able to get to the car until this afternoon, so I just took a quick look at the relay. Does the one in the picture look correct? That's what I currently have as a relay for my windows/doors.

The Forgotten On

That relay is incorrect. The correct part number on a Porsche relay is 928 615 116 00.

The toggle that represents the switch inside of the relay will switch in between two of the pins on the bottom of the relay. 87, which is always in a 4 pin relay and 87a which is on one of the 5 pin relays.

The one in your picture is a normal 53 (4 pin) relay. With that relay you will only have power going to the windows.



With the relay I described, you will have power going to the door locks when the car is off and power going to the windows when the car is on. It just switches between either circuit.

Simon928

Well that just saved me a ton of troubleshooting! Thanks so much for taking the time to explain how the relay works. I was only aware that this particular relay controlled the windows (that's all the manual says), so I never knew to even look there as a potential source of the problem. I'll be ordering a new relay ASAP. Again, thanks so much!

The Forgotten On

No problem.