Hi all,
I could really do with some help diagnosing my dynamic seats that have stopped working on my 2007 CL600.
I've read codes:
9250 - Pressure build-up no possible due to a leak
9260 - There is a danger of overloading (stored)

I've erased the codes and then, in live acuations / values, I can operate the pump manually and there is no pressure build up (it stays at 0 and you can't hear the pump running). Then after awhile (10-20 seconds maybe) it will re-store those codes and won't let me manually operate.

I can hear the valve operate (actuate and release on command) from the boot but the pump itself doesn't appear to be opperating (which makes senes with it not building pressure and storing that code).

I've checked fuse 127 (rear module behind the rear arm rest) which should be the DSP pump..... Any thoughts of what to check next?

Thanks in advance!

 

So wen't back out there.... connected Xentry again, same result but the first time I connected the pressure was 80 HPa which I thought was odd and it dropped to 0 when vented (predictable)... I think this is because it was a hot day and it's holding pressure so had just increased a bit (normal pressure is 2000, so 80 isn't much).
I also noticed in Xentry that the temp seemed a little high (there's two temps I think one is PCB the other maybe motor)... they were at 40C and 50C.... It was high 20's outside so I figured maybe it's just got very hot in there (more on that in a bit)...

I went through one of the Xentry test processes where it says to check voltage on the terminals to the pump. So I pulled off the back pannel of the boot/trunk liner (where the seat backs are) - this has no screws it's just held in by pressure fit on both sides and top (though there's also a felt flap that could be under the boot base) - felt like an idiot when I found that out having pulled most of the boot appart trying to find the pump in the first place.

I started removing the pump which you don't have to undo any bolts just gently yank and it comes out with it's insultation. I immediately noticed it was warm in one corner (but no signs of over heating). I prised out the connector and tested the pins 1 & 3 and they had 12V. Whilst I was there proding around I spun the fan (which is visible on these later models) and it fired up, built up pressure (it ran longer than I thought it should be and then stopped in the 1700-1800HPa range.
I then tried to turn it on and off (in actuations having vented it) and it wouldn't restart, but again by spinning the impeller manually it started again... so I think the motors probably weak. The rest of it looks goldern so currently weighing up options of new complete unit from Benz, second hand ebay unit or just replace the pump (aliexpress)...

Though, oddly I also have an old R230 unit which appears to have the same pump so might try a transplant!

FYI the heat was comming from the solenoid I think in the top right (vent probably?), which I presume is sprung open and held closed causing the predicatable heat in one corner...

 

So.. the motors are not interchangable the earlier r230 pump doesn't have the rear drive for the circulating fan... However I decided to disassemble the impeller component, which is wild (appears to be fully carbon impeller with free moving/wearable blades)... and some cumbs fell out so I might try to rebuild it and see if they were jaming it...

 

I rebuilt it (without the crumbs) and it seems to work. 20sec approx to get full from empty - no idea if that's good or not.
So I guess that's a win... for now!

Now I've just got to diagnose the original problem with the driverside bulster (side) supports... either going to be damanged air bladder or pipe hopefully...

 

With the pump running (barely - sounds awful) was able to track the air leak to deep in the left side bladder, so I'm not looking forward to dealing with that....
However I rebuilt / cleaned the motor for the pump out which was a tough job but it's gone back running almost silently which is really promising... just followed a load of online guides, some brute strength and a lot of idiocy...
As you can see the motor needed cutting open with a dremal, I've seen people prying them open with side cutters but I didn't manage that, it could then but hammered out.
Using a drill I sanded the armature and sprayed it all down with electric clean, including the brushes which were a bit sticky...

The sharpie I used to mark the locations of everything came off so took a copule of efforts to rebuild... Getting the inner key off and back on was a nightmare, but I did use a soldering hotair gun on high and levered with screwdrivers.
I also lightly sanded the carbon surfaces.

But it all went to back together and now starts everytime and runs silently...

 

Further to that I was mostly inspired by this:
https://www.benzworld.org/threads/ps...rhall.1563160/

and
This:

 

Further to this... confirmed it was the left driver side bladder that was the problem...
Got it out and tried a halfords tyre repair kit which was no good at all - I think the glue is specific for rubber.... Second attempt with loctite all purpose glue (for rubber, plastic, etc) and a piece of latex glove... seems to be holding



That was all a massive mission... One of the worst parts is getting the elastic strap back under the seats - for which I used cable ties to pull them throw, which defo helped (also it's worth bring the seat forwards and the seat back back to make the most space under the seat and relax the elastic).

Hopefully won't have to do that again soon!

 

Having gone through something similar with a 215....my advice is to get new bladders while they're still available. The plastic degrades in time, probably more in temperature extremes and swings, and literally crumbles to nothing after a while. So, once the cracks start it'll be an ongoing process. The second piece of advice is to simply remove the entire seat top cushion. It comes out in about 10 minutes and makes these repairs a breeze.

 

I have just bought a 2007 CL65 and I seem to be having the same problem with the dynamic functions of both front seats, strangely the only thing that works is the passenger massage function, everything else reverts back to 0 if I change dynamic bolster ect.
Booked in at Mercedes for diagnostics in a few days.