Mercedes R129 Roof Issues

[Alexgwmmm]

Hi guys,

I recently bought an R129 which apparently had a working roof, when I actually got the car though it won’t go up or down.

It seems to look like an issue with the window switches to me as it stops right when it would look to see they’re down.

My car has the limit switches fitted being 1994 rather than the hall sensors, although the module I have fitted is a 1298203226 which I think looks for hall sensors, can anybody tell me whether the module would work or if the previous owner has maybe put the wrong module in?

It shows the hall sensors not normalized fault codes sometimes but not all

Thanks
Alex

 

[Wearsafoxhat]

Electrically, I would assume that the wrong module has been fitted.
The limit switches presumably give an open or closed circuit, as don’t think that there are End Of Line resistors in them.
The Hall sensors will give a resistive value, however am no expert on these 129’s. You seem to be quite confident though, hope you get it sorted.


Sent from my iPad using Tapatalk

 

[LostKiwi]

Simple test is to push the window switch fully and if the window auto opens to the fully open position and stops the module is working correctly but from what you've said I'd say it's the wrong module that's causing issues.

 

[Alexgwmmm]

Yes the windows don’t work in one touch, they just go down in 2 inch increments

 

[LostKiwi]

There's the proof then.
Does the roof operate if the windows are fully lowered?

 

[Alexgwmmm]

No the roof puts the windows down as it should and then when it gets to the stage it should release the windscreen bar it stops.

When the windows are all the way down and pressing the limit switches they won’t go back up again until the limit switches are disconnected.

My car is in the changeover year so has the 2 connector module and separate roll bar module, does anyone know what part number would use limit switches rather than hall sensors?

 

[LostKiwi]

You'll probably need to speak to Mercedes.

Mercedes-Benz Teilekatalog (Ersatzteile online)

mb-teilekatalog.info

 

[Alexgwmmm]

Mercedes seem to think it’s the correct unit, but can’t give me any more information or wiring diagrams annoyingly, surely one of the modules would work from limit switches, but I don’t really want to buy them all to check lol

 

[LostKiwi]

Where is that module located? I can take a look at my 1993 SL this weekend.

 

[Alexgwmmm]

It’s under the rear seats

 

[Alexgwmmm]

That would be handy, mines a 2 plug module so it’ll be interesting to see if yours is the same and what part number it is

 

[LostKiwi]

Ok will take a look. May not be until Sunday though as I'm 600 miles from it at present!