Hi all
I picked up a 99/00 model is200 recently that has a sunroof that is not working.

When I press either the tilt or open button you can hear the motor start and then it stops with no movement of the glass at all.I have checked the 30A sunroof fuse and its OK, and the 10A ECU-IG fuse is also fine. I believe there is power to the motor just fine. If I do this while the car is on but not running I can see the dash lights briefly dim slightly when the motor starts - so it kinda looks like the motor wants to work but is jamming up or its just normal and the motor is hitting a limits switch or something - either way, to me it indicates that a decent amount of current is being drawn as opposed to just some control circuit energizing.

I pulled the motor out and checked the brushes and gearing. There was a bit of dirt there and while the motor spins freely, the gear that mates into the roof mechanism was a little rusty and very dry. Cleaned it all up and re-installed it all with the exact same results.

Were do I go now - can anyone recommend some further checks to do?I have seen a few comments around that talk about initializing the ECU that runs the roof, but that seems to start from the tilt open position - and I can't get to that position yet so I think that initialization is not the issue yet. Do these sunroofs have a habit of jamming up in the mech - do I need to pull the roof apart now and lub it all up and make sure its moving or is there some other simpler check/step I can do.
Thanks everyone
Mick

 

It sounds to me like it might be stuck by a dried up booger in there. You should probably try to "help" it open while actuating the electronic motor for it in case the seal is stuck.