W124 Cabriolet Roll bar pump problem

[Polak]

I posted recently re a problem with the roll bar on my W124 cab and after much head scratching and searching with local MB expert (Non dealer) we have found that it looks like the Hydraulic pump is u/s !!!!

This is a real problem as stealers want £2370 for a new one !!!!!!!!!!

First Q has anyone had this problem before and does this sound likely as the fluid reservoir was low and the roof operation was fine and problem only occured when roll bars were extended ??

Does the hydraulic pump drive the roof as well ??

Any info on less expensive replcement pump gratefully recieved part no 1248002348.

Thanks in anticipation

 

[Dee-124CAB]

If the fluid was low, have you tried topping it up?

If oil was low as you say...Have you seen evidence of a leak in the system like a puddle of fluid ?

No point buying a a new pump if theres a leak in the system elsewhere.....

 

[Polak]

Yes checked fluid and all ok with no leaks.

System has been checked and problem appears to be with the Hydraulic Pump so it's on it's way to BBA-Reman for check and repair.

Fingers crossed !!!

 

[bh13coupe]

one one ebay at a BIN £847
1248002348 Pumpe Hydraulik, Verdeck, Überrollbügel R129 on eBay (end time 18-Apr-10 15:00:18 BST)

add says its for a r129 but quotes the w124 code

google translate will sort the german out

 

[Polak]

W124 Cabriolet Roll Bar problem

I had the pump checked out by BBA Reman and apart from an apparent connection problem it has been passed AOK but has not fixed the problem !!!

My local MB guy is now telling me it could be the Roll Bar Control Unit but he is still not 100% sure as he has managed to get some movement up and down on the roll bar by disconnecting and reconnecting the control unit !! Having looked at how this all works I'm not convinced how he is diagnosing faults on the system as it has an EEROM store for faults so should be able to work exactly what is wrong, I'd have thought ???

This is a link to the W124 maintenance manual description if anyone cares to enlighten me as to how to fault find this problem.

http://www.ps2cho.net/downloads/MB CD/W124/w124CD2/Program/Chassis/91-800.pdf

Any input appreciated as I'm scrathing me head on this one .

 

[jaymanek]

Its not always that simple.. there are a few sensors that could be causing the problem too.. We had a similar issue with a CLK (which is a similar system) and after Mercedes Main Dealer threw about £2000 worth of parts at it, it turned out to be a sensor for under £20..
I ended up paying around £700 after serious arguments with them..

(this was before we had a star)

 

[Polak]

The continuing saga of the rool bar problem looks as though it could be the Control Unit but I can't find the correct part numbers as any reference I find seems to be for the Roof Control Unit and as the two appear to work together in certain situations it difficult to be sure which one is at fault and I can't locate the part number.

I'd appreciate any pointers to parts lists for this please as the one I have does not show it !!!

 

[grober]

The Rollover bar and Softtop control units do talk to each other so a fault in one might prevent the other from functioning correctly. Have you checked the adjustment/ state of activation of the rollover switches on the rear suspension arms? I think?? the softop control unit is located behind the offside [RHD] trim panel under the rear retracting side window. It is unfortunately subject to damage from water ingress which may be the cause of your problem??

 

[Polak]

Yep that's the one we are waiting on from friendly parts supplier who is "loaning" us his test unit to make sure it's at fault !!!

The Roll Bar control unit sits in the middle of the floor pan but I can't find a part number for this so any pointers would help ???

My Inde MB guy says these systems are usually rock solid but my 15 yr old baby has been in moth balls for quite a while and has a few Gremlins which I'm slowly getting sorted but fix ing one I find another, hey ho.

 

[grober]

The w124 cabriolet may well share this part with the r129 [SL] of this time- think its basically a latching mercury switch circuit. . If so ??? then PART NO might be MB 0038206810 or Bosch 0285001016
sometimes these crop up on German ebay
e.g. Steuergerät Überrollbügel DB R 129 W129 SL 0038206810 bei eBay.de: Autoelektrik (endet 11.05.10 19:06:30 MESZ)

 

[Polak]

Thanks Graeme,

Just waiting on parts man to turn up with the roof control module today and then we'll have a better idea of what's what !!!

JanZ

 

[Polak]

It's sorted !!!

Well talk about a long winded saga but finally got to the bottom of my soft top/rollbar problem after going down numerous dead ends finally got it sorted by replacing the Roof Control Unit which we had already replaced with a "test" unit from a friendly source but had failed to fix the problem !!!

After much time wasting and head scratching we got hold of a 2nd unit and it worked so this has now been replaced and all is well.

Thanks for all input recvd and if anyone needs a 2nd hand Hydraulic Roof Pump (#124 800 23 48) then I have one and it work fine. :bannana:

 

[dinoy]

polak i am trying to pick yr brains but do not have 30 posts so we can not email u my mobile 07940 280028 or email us through [email protected]