Hello folks, I spent a couple hours trying to get my front sunroof to work on my disco 2 last night with no luck. I can hear the ECU working when either the front or back sunroof is used but the front one doesn't want to operate (the back one does). I took the motor apart and cleaned all the gunk I could get at off of the coils.

Once everything I could get at looked clean (there was originally some gunk and corrosion in there) I re-assembled and re-installed the motor to see if it would do anything. The coil section of the motor started getting hot when I held the switch down so I'm thinking the issue is in the spinning gear section rather than the coils.

With all that said, is there a way to dis-assemble the other side, should I try and just spin that gear a bunch to loosen it up, or am I going to need to find an OEM motor from a junkyard?

Any help would be appreciated.

Thanks!

 

May be worth troubleshooting the motor by plugging it without installing it before buying a new one - just make sure that after testing, you put it fully back in the closed position (so that when reinstalling, the ECU doesn't think the sunroof is open when it's actually fully closed). This would at least check the motor operation itself independent of the sunroof rails, which have plastic guides that can break and seize.

 

Is the little gear supposed to spin when the sunroof switch is engaged? I can tell there's electricity getting to the motor but nothing is spinning or really "doing" anything other than heating up.

 

The gear spins and turns the two spiral coils of wire in opposite directions, which push the glass mounts through the sunroof rails. I suggested testing the motor while it's not installed to see whether the issue is the motor itself or a seized sunroof.

Lots of folks will probably recommend leaving it alone, in case the worst happens: the sunroof opens but then refuses to close.

 

I'm thinking that's probably the right move, I'll take the minor victory of having 1/2 working (20-year-old) sunroofs and leave it at that. I like the idea of having the front one operational but as you say, there's more to lose than gain here.

Either way, I appreciate the suggestion and I will go ahead and test the motor separately to see if I can at least determine where the issue is, in case I want to attempt the fix down the line.

Cheers!

 

Those motors are pretty complicated, are you sure you got the brushes reinstalled correctly? It the armature was rusted/seized to the housing that was likely your problem originally. You should be able to easily turn it by hand with the worm gear installed in the drive housing without the magnet housing on.