R170 Vario Roof Problem...

[tomkeeling]

Hello all,

Just had my 170 1999 230SLK in at a recommended independent Mercedes specialist to resolve an issue. Basically when you press the switch, the light flashes but nothing happens at all - no whirring no movement of anything no nothing.

The garage found some stored faults and cleared them, opened the roof and closed the roof fine. I picked up car, tried it, still nothing. Prior to this fault, the roof had worked fine.

The fault code is as follows:

"B1271 Components S69/1 (Vario roof closed limit switch (right lug)) and S69/11 (Vario roof raised/lowered limit switch) are operated at the same time. Current and stored".

So the mechanic opened it fine, closed it fine and then the fault re-instated itself, and if I interpret the fault description something is faulty with the right lug closed limit switch.

My garage have accessed and tested the switches in question and have replaced one which repeatedly came up as faulty. They tested tested and tested more and all was well. Car came back and the roof still wouldn't work. Or, at this point, the window wipers either. Now I understand these are controlled from the same unit - 170 820 09 26 - so I tried a spare unit at the garage and both the wipers and the roof worked. Put my old unit back in, and initially the roof worked numerous times, and the wipers worked. No faults on the star fault diagnosis.

Drove home. Wipers still work but roof doesn't. I removed the control module and had a look inside. Can see no loose components, the relays moved freely etc etc. Put it back on and no change. Am I correct in thinking this box is the root of the problem? If so, which relay in it controls the roof? Anyone got any ideas?

Cheers Tom

PS I have searched the forum and found quite a bit of useful help but not quite enough!

 

[Alex Crow]

the microswitches are well known for sticking on these cars - various ones, and there are many. i suggest you change whichever switch was not changed already but listed in the fault code. note that S69/1 is located at the RH catch at the top of the screen, and S69/11 is by the RH pivot assembly - near the belt loop behind the drivers right shoulder, you may already know this.

as for the wipers, probably a red herring. they likely will not operate with the roof in a an intermediate position, or if it THINKS it is in an intermediate position.

 

[television]

Not sure on this one, if it is not a switch then I can check to a certain degree the control box, I would check on the other one to see if the roof worked again first

 

[tomkeeling]

Hi,

Both suspect switches have been checked and once the fault codes are cleared in MB Star, all works fine, and you can actually 'see' the switches working on the screen. It seems that it is after the fairly long drive back that it all stops again. Could this be heat related somehow? Is there any way I can reset the faults because at the moment unless I go back to the Indy I can't operate the roof so can't even look at the switches myself. If this can't be done, I was wondering if anyone has the kit to reset the codes for me? I'm in Warwickshire but could have a trundle out somewhere.

Very very annoying! I appreciate the input from you all. Oh there was one other thing - when we took my original module out it had some writing on it in marker - it seems it had been out and checked before which makes me doubly suspicious....

Thanks,

Tom

 

[BlackC55]

I had one that behaved just like this. I found a broken wire in the roof hinge.

It was an arse to find