jamesbrew

My anti roll bar on my CLK 320 (W209) wont stay in the up position. The other one works fine. One day it just stopped, nothing in particular happened. There are no warnings on the dash.

I'm wondering if any one has experienced this before, and if you have, what did you need to do to fix it.

Thanks

Plutoe

You obviously have a fault in a very complicated electronic system---see someone that can read the MB chassis faults, OBD can't, then fix the fault.

jamesbrew

No warnings in the cluster and the other one stays up no problem. It's missing the mechanical clicking sound as I pull it up that the other one has. I doubt it's electrical somehow.

Yidney

I think you will have to pull the back seat and investigate how it works. I think you may be right that whatever mechanical device that holds it up has either broken or come loose or has a dead squirrel stuck in it. I have a sightly different issue. Mine work fine, but even when fully down, I occasionally get a message telling me to lower them. So far it's too occasional to care about. If you need any instructions on how to remove the seat, I can tell you that. I've had mine out several times.

Yidney

It's also possible that whatever electrical device allows them to lower is stuck, so it has the latching mechanism pulled out. As you know, when you release them with the console button, they drop like a ton of of bricks. It always made me laugh that a Mercedes does that. I have always pictured some device that yanks a lever away like on the trap door of a guillotine.

jamesbrew

Yeas, they do go down with a bit of a bang ok. I'll have a go and see if I can get the seat off. It's always nice though if you know what you are looking for in these matters.

Yidney

Honestly, the hardest part about removing the seat is not breaking the little plastic covers over the four bolts that hold the lower seat cushion in. Like many plastic car parts, they are under-engineered, and you cannot see how they are held on. There is a hole in the bottom that you are supposed to press up lightly with something like a small screwdriver to release a catch while pulling up and forward. Once you break the first one, you will then see how they work. Luckily, they are ABS plastic, and a drop of super glue will make it reusable. Then it's just matter of removing the two lower seat belt bolts, and the other bolts/nuts that hold the seat bottom and those heavy baby seat brackets. Then the seat back pulls straight up. The main things holding it are near each end, not the middle. They are these large plastic blocks the seat snaps on to. Just give a stiff yank up on the ends. Once you are that far, not sure what else you may need to do. But if you get it apart, appreciate it if you could post up some pics of what electrical things hook up to it and where they are.

Rudeney

I replied on benzworld, too, but for others who may run into the same problem...

There is a spring loaded pawl that ratchets as you raise the headrest. My guess is that it is either broken or stuck. This should have no effect on the emergency roll bar operation as it uses a different mechanism. Try pressing the headrest button on the dash a few times to see if it's just stuck and will release. If not, you'll have to disassemble it to find out what is wrong. Unfortunately, each side's the rollbar/headrest is all one assembly and individual parts are not available, so if the pawl is broken, you'd have to replace the entire unit or improvise something yourself.