Boxster/996 window issues?
I have seen a lot of window issues in boxsters and 996’s lately. The general operation of the door glass is simple in the 2 cars. Basically, when you pull the the door handle (inner or outer), the window glass will drop about a 1/2″ to allow for smooth opening of the door. When the door shuts, the window will raise back into place. The same goes for the convertible tops. When the front release handle is triggered, the windows drop to allow smooth opening and closing of the top.
Now there are several ways the window operation can fail (IE, not drop when you open or close the door, or convertible top).
There are 3 microswitches in the door. One is triggered by the inner door handle, telling the window to drop when the door is opened from the inside. A 2nd microswitch handles the same operation from the outer door handle. A 3rd microswitch is found in the actual door latch mechanism, that tells the window to stay down if you let go of the inner or outer door handle while the door is open.
So some failure modes:
1. Door glass does not drop when opening the door from the inside: Culprit–inner door handle microswitch
2. Door glass does not drop when opening the door from the outside: Culprit–outer door handle microswitch
3. Door glass goes back up when you release the either door handle, making it very difficult to close the door with the glass all the way up: Culprit–door latch mechanism microswitch
4. Both door glass windows do not drop when operating the convertible top: Culprit–Convertible top latch microswitch
Recently I had a #3 come through the garage. The bad thing about #3, is that the microswitch is built into the door latch mechanism, so you have to replace the entire unit if it is bad. The other microswitches can easily be replaced by themselves.
Replacing the unit involves removing the inner door panel. There are numerous hidden screws and clips that need to be conquered. Once the panel is out of the way, you can remove the door latch mechanism. It is a tight fit, but it will come right out.
Looking at the inner door panel……the mechanism is hid back in there……
The assembly out of the car. Notice the blue and red wires attaching to the microswitch.
You can see the two small holes that help hold the microswitch in place. The switch rides on the round cam gear. In this case, the cam gear (which is plastic go figure) started to separate, and the microswitch no longer operated on material that wasn’t present anymore.
Now the switch is very easy to test in the car. You can open the door, pull the latch mechanism partially out (leaving the electrical connections in tact), remove the microswitch from the assembly, and push the button. If the window drops when you push the button, then you have found your problem. I tried to repair the cam gear in this instance, but the gear was so deteriorated, that it was impossible. So a new one is on order!