SL/R230: Driver Window problem
The driver window on my car started behaving eratically, it would not respond to switch inputs, then it started moving randomly in the opposite direction. Ie if I selected up it would move down.
Then finally it’s stopped moving at all. Won’t do the 1cm drop either when you open the door either.
I’ve checked fuses which are all OK. Any ideas where to start investigating? Which modules should I look at.
thanks, Mat
here some prints to help you open up the door
If you have Xentry/Das, you can diagnostic this in minutes with Test, Actuation and Actual Values
always mention Make Year when it come to electronics
Last edited by pmercury; Dec 19, 2020 at 04:59 AM.




Erratic behavior sounds like a bad module for the window controller, or relays in the controls.
If I were using Star Diagnosis, from the main menu for the door control module I would go to Actual values > Power windows > Relays, switches, operating elements. That leads to the screen seen below which shows all of the basic info to troubleshoot this problem: The current drawn by the motor, whether or not motion is blocked from an obstruction or the roof controller, and the input from the window control switch. It's apparent that the software for the Foxwell is patterned after Star Diagnosis, so I'd expect all statuses seen below to appear with the $110 tool.
As mentioned before, you can not control the window motor from Star Diagnosis. The motor can only be actuated from its control switch on the door panel.
Finally got around to digging into this as the weather is improving.
I can confirm my Foxwell gives me the same screen checks as above. Ive been through them all and all relays, switches are activating and showing normal, however current consumption is a big fat zero.
So some follow up questions.........
1. Is this starting to feel like a motor issue?
2. I can't get out of my head that just before the failure the window had started working erratically, up when commanded down and vice versa etc. In my experience if a window motor goes bad it just stops working. While I look at getting the motor out is their anything else I should look at controller wise?
Many thanks in advance for any help.
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The driver window on my car started behaving eratically, it would not respond to switch inputs, then it started moving randomly in the opposite direction. Ie if I selected up it would move down.
Then finally it’s stopped moving at all. Won’t do the 1cm drop either when you open the door either.
I’ve checked fuses which are all OK. Any ideas where to start investigating? Which modules should I look at.
thanks, Mat


