Sunroof fault

[Ferret]

Anyone know what would cause the sunroof to start playing up?

It wont auto park any more and it's infuriating. Only the forwards/backwards button works, the 'up' button doesnt do anything anymore.

I seem to remember that pushing the button forwards should always make the sunroof return to the closed position, but instead it closes and just keeps going opening the sunroof into the tilt position!

Any ideas what's causing this?

[BennyM]

It sounds like the "up" command is now tied to the "forward" action of the switch. My guess is it's a bad switch or relay issue. Pop out the sunroof control panel to see if any water has leaked onto the switch. Or maybe a wire up there is broken or touching something it shouldn't be.

I'm not sure where the relay is for that, but my guess would be under the rear seat. You can take the rear seat out and run the sunroof to see if anything clicks in the rear relay cluster.

Anyone know what would cause the sunroof to start playing up?

It wont auto park any more and it's infuriating. Only the forwards/backwards button works, the 'up' button doesnt do anything anymore.

I seem to remember that pushing the button forwards should always make the sunroof return to the closed position, but instead it closes and just keeps going opening the sunroof into the tilt position!

Any ideas what's causing this?

[Ferret]

It sounds like the "up" command is now tied to the "forward" action of the switch. My guess is it's a bad switch or relay issue. Pop out the sunroof control panel to see if any water has leaked onto the switch. Or maybe a wire up there is broken or touching something it shouldn't be.

I'm not sure where the relay is for that, but my guess would be under the rear seat. You can take the rear seat out and run the sunroof to see if anything clicks in the rear relay cluster.

The switch is brand new for the sunroof!

However... I've noticed that in the trunk on the left side there's a relay/fuse panel with one particular relay removed and jumpered with a piece of wire. I've a sudden suspicion that this is probably what's causing it.

The E31 has it's "under seat" relay/fuse panel shifted into the left side of the trunk, as there's not enough space under the rear seats.

I'll pull that piece of jumper wire out this evening and see if the sunroof suddenly packs in. If it does, I know what the problem is!

Also, does anyone know if there's a relay diagram for the E31 knocking around on the web?

[whiskychaser]

Had a similar problem which I put down to lack of use Cleaned the runners and used some silicon polish on them. 6 months later and it still works fine

[bubba966]

Also, does anyone know if there's a relay diagram for the E31 knocking around on the web?

Might be one here http://www.wuffer.net/

Lots of E31 stuff there...

[bubba966]

There's relay info here under the electrical section. http://www.bmwtechinfo.com/repair/main/721en/index.htm

[632 Regal]

try holding the switch in the forward position for like 30 seconds, worked like magic here.

[Ferret101]

Cheers guys, I've tried resetting it now using the hold the button down in the up/forward position for 30 seconds (and I heard it trip, so I know it worked) but it's not made much difference.

I suspect either the motor is badly positioned or the internal microswitches have packed in...

[Ferret]

Er, wonder what the hell happened there, it let me log in as Ferret101 (used on another forum!) I must have registered a double account by accident!

[Ferret]

Figured out what's going on with the sunroof anyway.

At some point in the cars history the control unit must have failed - someone's dismantled it and hotwired the relays inside it.

It's basically set up now so that just the forwards and backwards buttons totally ignore any logic in the unit and manually activate the drive.

Wonder if it's the same unit in an E32 and E34... with have to have a nosey then ebay a spare