Troubleshooting window sensor

[Timfitz]

I have a 99 Boxster and my window's are going up and down as I am driving over bumps and around fast turns. It is not the convertible sensor, but something that is in the door. When you open the door to get in or out of the car it lowers the window about 13MM then raises it once the door shuts. That is what is occurring while I am driving. Any idea on how to fix? Thanks in advance.

[Tool Pants]

Is your top up and latched when this happens. If the top is down does it happen. What sensor do you think it is not.

Might be this.

Peter

[Timfitz]

Yes, the top is up. I had the problem with the top sensor where both windows would come down and stay. It was the sensor under the top latch that was bad. I fixed that one. This occurs on the driver side window only when driving. The window goes down and up like I am opening and shutting the door. If you pull the door handle open you get the same action from the window. The problem is that I am not opening the door, it occurs while driving. Very bizarre ;) Any thoughts would be appreicated. Thanks.

Fitz

[Tool Pants]

With that added description this is a new one for me. I will put it on the Peter list. My only guess is that there is something wrong with the microswitch in the door handle. It is that switch which does the window drop when you open the door. You might want to remove the door panel and replace the switch and see if that fixes the problem.

[doughep]

my window's are going up and down as I am driving over bumps and around fast turns.

<{POST_SNAPBACK}>

I'm just guessing here, but I wonder if it's a loose connection to the microswitch Toolpants mentioned. The problem only occurs on on side, and on bumps or during turns that would cause the car to lean. If a momentary disconnect of the connection to the switch reads as 'open', it sounds like a possibility. My instinct would be to take off the door panel, turn the key and jiggle the wires to the switch and see if it behaves as you described.

Then again, I wouldn't want to get hit in the face with an airbag - they tell me that stings a little.

Good luck.

- Pete

[Jinster]

I have a very similar problem. Only the driver's side window. It lowers when I open the door, but it then goes back up again before I can close the door. So I end up banging the top window edge against the plastic covertible strut all the time. Does yours do that? And where would this micro switch be located?

[txhokie4life]

I have a very similar problem. Only the driver's side window. It lowers when I open the door, but it then goes back up again before I can close the door. So I end up banging the top window edge against the plastic covertible strut all the time. Does yours do that? And where would this micro switch be located?

I know this was a long time ago -- but my sister-in-laws car did this tonite.

what was the solution?

m

[1schoir]

I have a very similar problem. Only the driver's side window. It lowers when I open the door, but it then goes back up again before I can close the door. So I end up banging the top window edge against the plastic covertible strut all the time. Does yours do that? And where would this micro switch be located?

I know this was a long time ago -- but my sister-in-laws car did this tonite.

what was the solution?

m

Mike:

When the window goes back up that 1/2 inch while the door is still open, the problem is usually caused by a fault in the door lock assembly. Sometimes the connections or the microswitch will be intermittent or one of the wires leading to it has become chafed or pinched (and thus causes a short) and sometimes the solder connections inside the assembly crack or come apart. Porsche only sells the complete assembly (), but you can take the housing apart carefully and resolder the connections. One poster on 986forum ("Jinster"), who also posts here was even able to re-flow the solder to those joints WITHOUT taking the housing apart.

Here is a photo of the inside of the assembly (courtesy of "sb01Box"):

Regards, Maurice.

[txhokie4life]

I have a very similar problem. Only the driver's side window. It lowers when I open the door, but it then goes back up again before I can close the door. So I end up banging the top window edge against the plastic covertible strut all the time. Does yours do that? And where would this micro switch be located?

I know this was a long time ago -- but my sister-in-laws car did this tonite.

what was the solution?

m

Mike:

When the window goes back up that 1/2 inch while the door is still open, the problem is usually caused by a fault in the door lock assembly. Sometimes the connections or the microswitch will be intermittent or one of the wires leading to it has become chafed or pinched (and thus causes a short) and sometimes the solder connections inside the assembly crack or come apart. Porsche only sells the complete assembly (), but you can take the housing apart carefully and resolder the connections. One poster on 986forum ("Jinster"), who also posts here was even able to re-flow the solder to those joints WITHOUT taking the housing apart.

Here is a photo of the inside of the assembly (courtesy of "sb01Box"):

Regards, Maurice.

Where is that assembly -- is it behind the door panel -- back along the end of the door?

I've taken a couple doors apart -- but its been awhile and it was for something else (broken cable)

thanks,

mike

Edited December 15, 2010 by txhokie4life

[1schoir]

Where is that assembly -- is it behind the door panel -- back along the end of the door?

I've taken a couple doors apart -- but its been awhile and it was for something else (broken cable)

thanks,

mike

Mike:

It's behind the door panel, here (click on the photo to get a good look):

Regards, Maurice.

[txhokie4life]

Where is that assembly -- is it behind the door panel -- back along the end of the door?

I've taken a couple doors apart -- but its been awhile and it was for something else (broken cable)

thanks,

mike

Mike:

It's behind the door panel, here (click on the photo to get a good look):

Regards, Maurice.

Dang -- looks like another door dive.

BTW, anyone know if the cable from the door latch to the door handle is a replaceable item?

I had to canalbalize my race car awhile back -- but now need to put the race car door back together.

Mike

[Jinster]

The Bowden (or is it Bowen?) cable is a purchasable item. There was one for sale on eBay not long ago.

There are two microswitches - one on the inner door handle, one on the external door handle. Maurice's picture actually also shows where the external handle microswitch is attached. The internal microswitch position would be very obvious once you open the panel. Either of these could be faulty/loose. Just disconnect one and then the other (or both) to diagnose your problem.

Another failure point is the connector at the door lock mechanism - wiggle it at the connector and see if you can reproduce the problem.

This won't be too hard at all.

[RFM]

There are 3 micro switches on each door to be correct, 1 on outside handle, 1 on inside handle and 1 inside the door lock. The one build in the door lock is the most vulnerable in the system.

[Jinster]

My post does refer to a third "failure point" inside the door lock mechanism itself. I am just not sure if there is actually a physical microswitch inside the DLM. It's certainly a "microswitch by principle". The DLM would sense if the door is open - by the way of the switching plate's position - one can simulate a door closed position by manually flicking that switch plate in the exposed part of the DLM when the door open. I am just not sure if the flick of that plate actually actuates a microswitch. It's probably a direct switching effect. But the result is the same. And the DLM is difficult to service. If the DLM is responsible, the failure point is usually not at this "microswitch by principle" but rather at where the harness connects.

Anyway, I just noticed that I was one of the original posters of this thread, back in 2004. And I just fixed this problem I posted about then, a few weeks ago. It took me 6 years to get to it! Haha....... :)