Multiple projects going on with my 01 XK8 Coupe, but the one that is the biggest nuisance at the moment: the windows.

Sometimes my windows work just fine. Sometimes they don't work at all. Today when I opened the door, the left (drivers side US) window decided to roll itself all the way down. Then a few seconds later, all the way up again.

Sometimes they roll down when I open the door, sometimes they don't. Sometimes they won't open at all.

Sometimes one window will work but not the other. If the right window decides not to work, it won't work from either switch. It also seems that sometimes the only way get them working again is to open the driver side door.

​​​​​​They really seem to have a mind of their own.

Here's some info, all of which may be red herrings, but I'd rather give extra info than not enough:

​​​​The power locks are a little wonky. The power mirrors work MOST of the time. The memory for the steering wheel seems to have dementia, but manually adjusts no problem. All gauges work fine, but I've scanned a P1638.

I've tried the procedure for resetting the windows roughly eleven hundred times. I've tried a hard reset maybe half a dozen times. The battery is newer, I've trickle charged it and had it tested.

Anybody have a guess? I'm happy to throw a little money at it, but I'd like it to be smart money. Switch? Wiring harness? Microswitch? Some control module or something?

It's driving me crazy, so any help would be GREATLY appreciated!

 

What I found on my 96 X300 was a wire on the driver side control unit had become unlocked from the connector and making intermittent contact . Yours may be one of the shared control wires between left and right side doing the same putting the logic out of sequence . When you jar the door it might make the wire contact like it should and the resulting command is too complex of a concept for it to effectively deal with and go nuts . Just push in the wires on the connector backshell and relock the locking device . At least it doesn't tweet like our great leader when a wire is loose .

Free

 

You've eliminated battery so I'd then put microswitches top of the list. Next has to be the possibility of the door harness being damaged by flexing over the years.

Graham

 

Thanks to you both!

Quick question, is the control module part of the switch, or is it its own piece altogether?

Thanks again!

 

The door control module is mounted inside the door and the door card has to removed to access it.
GGG is most likely pinpointed your problem. If you open the door and examine the area where the hinges are you will find a flexible rubber connecting the door to the body. That contains all of the wiring entering the door. You most likely have one or more broken wires that are causing you problem.
Unfortunately you will still have to remove the door card and interior cover to access the wiring.

 

Got it, thank you!

Does that module ever fail, or not so much?

 

There have been some reports on the forum of failures but it couldn't be described as a regular issue.

Bad news is the Door Modules come out through the speaker apertures so there's quite some dismantling required.



The two harness connectors shown in the diagram will give you an idea of the number of leads going into the door.

Graham

 

Graham, that is super helpful! That doesn't look too scary. I'm sure I'll be swearing up a storm, scraping up my forearms when the time comes, but that's just par for the course!

 

A quick word of warning. Disconnect the battery before starting the dismantling. When working with module and hands in the door the window has been known to move.

 

Good point. And honestly, I wouldn't be completely surprised to find that the control module was replaced by a HAL 9000!