JeremyW964

OK, I turn off the ignition, start lowering the window on the drivers side and open the door and the window continues to go down. So I have a bad door switch, right? I have noticed that when I leave the car for more than 5 days then my battery get's run down.Again, because the door switch has not disconnected the circuit for blinkers, lights, etc, right? Has anybody replaced these? Where do you recommend for parts? How tough to replace? Thanks in advance!

Randall G.

Hi Jeremy,

You may have tried this already, but isn't just closing the door and watching to see if the interior light goes off an easier way to make sure the switch is recogzing the door is closed? Likewise, you can open the door and make sure the light comes on to verify the switch is recognizingg the door as open. Of course, this all assumes your interior light switch is in the "door" position.

Anyway ... I don't quite understand what the door-switch has to do with headlights, turn-signals, etc. I would think these only "care" about the position of the ignition switch, but I could be uninformed .

Premature battery drain seems to be a common 964 malady, and may have nothing to do with your door-switch.

JeremyW964

Randall -
Thanks for your reply - The interior lights have never worked (and I have never checked the fuse panel or bulbs). I will do that tonight when I get home.

- Jeremy

Jeff Curtis

Door switch replacement is VERY simple, it sounds as if your's is sticking. When I first bought my car, mine was sticking on the Driver's side...so I ordered a new one ($7 I think). Wouldn't you know that by the time the new switch came in @the dealership...it didn't stick anymore!?

So, w/my montra of, "don't fix what isn't broke"...the new switch still sits on my workbench.

Back to your question, the door switch is accessible under the "rubber", just pull the rubber off the lip/washer that is placed between the door switch and the door jamb. Unscrew the door switch and pull out, you will have to "un-curl" the terminal that holds the ground wire and basically crimp it into the new switch...not a difficult task.

As our FAVORITE tech manuals state, (Hayne's) "installation procedure is reverse of removal"...or something of that sort??

On another note, I don't believe your door switch is the culprit for your battery drain...all the doorswitch does is complete a ground when the door is opened and the switch "pops out". Your switch is either sticking in the depressed position or it is corroded and doesn't make good contact when it pops out, either scenario is fairly common.

From what I understand, the recurring culprit for battery drain seems to be the environmental controls panel...but don't quote me on that one!

I have a question for you, being that you are experiencing battery drainage...does your ABS light and audible alarm come on fairly often right after starting up your car?? I have heard of this and realized that was occurring until I changed out my battery. Just curious.

Adrian

Dear Jeremy,
Yes this is saying you have a bad door switch. The door switch provides an EARTH to the alarm system, the interior lights and to the power window regulator relay. If this earth is missing, most common cause the wire has fallen off the back, then the interior lights will not work, the alarm will not work and the windows can be powered up and down with the door open.
This cannot cause a current drain. To have a current drain you have to have three things. 12VDC, and earth and a resistive circuit. A short circuit blows the fuses or burns the 911.
There is no common cause of current drains. There are so many circuits which can cause this you have to troubleshoot it.
Battery running down after five days sounds like a trunk light or engine bay light remaining on. Disconnect the switches, very easy, follow wiring to connector and pull apart.
Ciao,
Adrian
911C4

JeremyW964

Thanks for the input! I guess I will have to get busy tracing down these wires... At least I know where to start.

To answer your question Jeff - when I start the car only the airbag light comes on for a second and the spoiler light stays on until I pull away. No ABS or alarm.

Jeremy Dixon
1990 C2 Targa "Neva"

Roland Kunz

Hello

Porsche has a widow doorlogig. Coming in the 80s.

The reson is that if you have pulled the key and see that you forgot to move your window you can do it as long the door is open and are not forced to return the key.

I´m not sure if the 964 has the one tip convience feature. The window will hang on the switch and stop if you release the switch. If it runs further on it must be a internal switch faulure.


If you remove the switch and the door is closed your switches shoud not work. They will work if your door is opend. The switches will also be powerless if you engaged the factory alarm. Even if you set the alarm with doors open. Depending on the version the alarm will wait to set untill the last door or hatch was closed and count 10 secounds down to set sharp and dead lock.

Grüsse
Grüsse

Iant

Ok, im coming in at the end of this discussion but can someone explain, if i open my passenger side door(it does not work with the drivers side) i can open the windows and sunroof. Is this correct,it seems strange just one door enables this. Or do i have a problem somewhere and any idea where to look?

Randall G.

Hi Iant,

With the key out of the ignition, driver's side door closed, I just tried opening my passenger door while lowering the window: the interior light comes on, the window quits lowering. So ... it sounds like something is amiss with your car.

Most obvious cause would be the door switch sticking. Does your interior light come on when you open the passenger door? If not, your switch is probably sticking. And, that's why you can still operate your window and sunroof ... the circuitry thinks the door is closed.

Hope this helps.

Adrian

If the window can be lowered with the door open then there is a problem. I have not checked the sunroof circuit because I do not have one. If I get a chance I will.
The 964 has no fancy systems installed to carry out this work. Just plain old 1960s vintage relay logic. There are no descriptions in any of the 964 manuals on the operation of this power window regulator relay either. Same with many other systems.
My Audi according to myth and legend has a motion switch in the door that stops the window from lowering. Some sort of impact protection device. Has never worked for me and cannot find anything about it either. I have tried everything to make this work. I remember the saleman trying to make it work, never did.
If the 964 series windows should still keep coming down or up when the switch is activated and you open the door at the same time and keep your finger on the switch (tough but doable I guess, I really do not know). I will give it a try one day,
Ciao,
Adrian
911C4

Roland Kunz

Hello

Ok this is out from memory
The 911/944/928 from 1986 on has a logig switch relay. It powers the fuse for the window lifter and the sunroof.
Those relays are different for the markets.

The logig uses the central lock /alarm, the doorcontacts and seatbeltswitchcontact to determine his action.

If the relay failes it would be the best it fails in a mode where you still can use the drives. Say it switches to full time power.

Just a guess. Can´t remember having trouble with them

Open your relay/fuse box and lock inside the cover. ther you will find a fuse and relay description.

Also read your manual if it descripes the normal action.

Grüsse

USCGMoose

I came across this rather old thread and decided to revive it since I'm having similar problems. It's funny, the more I read Rennlist, and the more threads I review, the more things I find wrong with my car!

OK here's what my car does:
1. All fuses 100% ok
2. Open either driver or passenger door and the interior light does not come on.
3. Interior light can be turned on manually but does not work automatically with the doors.
4. Open the drivers side door with the key out and you can still raise and lower the windows.
5. Open the passenger side door with the key out and the windows are disabled.
6. Even if you are standing there opening or closing the window with the driver side door open and somebody opens the passenger door, the windows won't go up or down anymore.
7. The alarm seems to work because I've accidentally set it off on myself a couple times. I don't recal if this is after opening the passenger door or not.

So, is the consensus a bad driver's side door switch? If so, is the fact that my interior light won't come on even with the passenger door open unrelated?

Thanks for the help.

Marc '91 C2 Coupe

Jeremy (and others)

You are NOT crazy!

I am here to say that you are exactly correct, because I had the identical problem. When someone else pointed it out to me (thanks again, Ed B.), it was an easy fix. Although I have not yet gotten around to replacing the switch, I at least now recognize the problem, and can do a fast fix whenever it occurs.

Ever since I bought my 964, the battery would go flat in less than 5 days, even with a brand new battery!

By the way, the driver's side interior light had never worked properly, so this should have been a giveaway.

A new PCA friend pointed out that he'd heard this story about the door switch, and we did a simple test: turned off ignition, and the driver's window still worked (it shouldn't).

Apparently, and maybe Adrian or someone more technically competent than me can comment, if the faulty door switch keeps the circuit closed, it continues to energize some of the car's circuits (like the window, and I don't know what others), and this sucks the battery dead in just a few short days.

We played with the switch for 5 seconds, and it began to work properly (although it has stuck on me twice since then, and I caught it both times).

Ever since the diagnosis, if the interior light fails to come on when I open the door, I just play with the switch a few times until the light comes on and the window will not work. Usually takes no more than a few hits.

Voila! No more dead battery...

Good luck,

Marc
<img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

USCGMoose

Thanks for the info Marc. Any trick to "playing" with the switch. I may need to get a new one... anyone know the part number.

Interestingly though, my interior light doesn't come on when either door is open (or both). The passenger door does disable the windows like it should.

Also I've let me car sit in the garage for a month and the battery has been fine. I did have to replace the battery once but I think that MAY have been unrelated.

At any rate, I think I'll need to replace the switch or fix it on the drivers side. We'll see what happens then.

Thanks again! <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />

Adrian

According to legend because I have never seen this myself, the power window regulator will allow the window closing action to be finished when the door is opened and after the ignition switch is turned off. I remember somebody telling me that your hand must never leave the window switch though. Once the window is fully up the window regulator switches off and you cannot open the window anymore. My 964 has never done this. Ignition off windows stay where they are regardless of door open or closed. Doors open and ignition on, I can wind my windows up and down whenever I want.
As for power or battery drains you need to check earlier posts or the archives. Thereis only one way to check for a current drain and that is to measure the current flow being drained out of the battery. Once you have established you have a current drain then you have to pull the fuses one by one to find the circuit.
The door switches themselves just switch earths. You also need 12VDC and a circuit for a current drain. So you have to find the circuit.
Most commonly the current drains are the luggage compartment or engine bay lights staying on all the time. If the interior lights are not on then they cannot cause a current drain. Intermittant activation of the lights is quite common because the switch mechanism and wiring is mickey mouse.
As i said one has to remove fuse by fuse to get the current drain down to circa 13ma to 90ma depending on equipment installed. To flatten completely a 70amp/hr battery in 5 days will take a current drain of approximately 0.6amps or 600ma. Funnily enough this looks like a lamp current draw.
As I said, you need a circuit for a current drain and even if the window power regulator is still activated it is just a relay so it draws very little current but if the window switch is not activated you have no 12VDC and no circuit. Now water in the door itself can cause a current drain. However that is a different story.
So get that multimeter out, get the current draw measured and take it from there. As for the door switches themselves. They are easy to replace, the ones you get now are off the 993 and the rubber boot supplied is useless on a 964.
Ciao,
Adrian
911C4