Question: When you raise or lower the roll bar (rear seat head rests), does the pump stop running when it is raised or lowered to its limit?

Issue: The other day my sister borrowed my 2003 CLK-320 Cabrio (W208) and when she tried to lower the top the windows went down, the rear bow lock cylinder released (at least partially, don't know if all the way), and then it stopped (with the bow about 1/2" above the deck). It wouldn't move either way after that and now the red light on the switch flashes slowly when pressed. She locked the front closed and drove it home.

When I tried to raise or lower the roll bar, it moves up and down with no problem, but I noticed when I moved the roll bar it caused the bow lock cylinder to actuate a bit (it seemed to pull the bow down a bit). When I hold the roll bar raise button it goes to the top and stops moving but I can hear the pump keeps running. Similarly, when I hold the roll bar down button, it lowers all the way but the pump keeps running until you release the button. I'm wondering whether this is normal, or whether it's supposed to shut off the pump when they are all the way down or up. I'm wondering whether I have a bad roll bar limit switch so the system doesn't know the roll bar is up/down and won't let the roof move.

I've since manually opened the deck and don't appear to have any leaking cylinders (I replaced a leaking bow lock cylinder last fall) and the hydraulic fluid reservoir is full.

I've swapped the fuel pump and roof relays to test the roof relay by the pump and that didn't help anything.

Any other thoughts/suggestions?

Thanks.

 

Pull out your seat cushion and back and see if your quick release cup has fallen off.

My roll bar popped up and I can't bring it back down. I hit a curb putting my right rear wheel in the air; safety measure in the car sends the roll bar up in a second thinking the car might roll over. The way to get it down normally in a w208 is to press up on the roll bar switch for 8 plus seconds until you hear a bracket engage. Then press down on the the same switch and it the roll bar will go down. Here is the problem in my case. There is a metal cup the is attached to the bracket in question that connects to the bottom of the drivers side roll bar. This metal cup unscrewed from the bottom of the headrest and now the solenoid can not reattach. Normally it is attached to a solenoid underneath. When the car thinks it rolling over the solenoid detaches and the large springs on either side of the roll bar send them shooting upward in a second or less. This is just another poor design or poor construction for our cabs. First the front handle is friction fit with a washer that breaks off; can be weld back. Then Benz uses a screw on cup that connects to a solenoid that is not set with either a lock washer or loc-tite.

I know my problem was not like others on the forums for two reasons.

1. Can't be hydraulic related; not leaking fluid.

2. Can't be relay; can hear the hydraulics being actuated when pressing the roll bar button.

Therefore, I took out the rear seat cushion and back rest. The back rest is four bolts on the bottom and two screws behind the center armrest backing. Then its a gentle tug hear and there. I found the metal cup and washer under the seat cushion. Therefore, if you haven't figured out your reason why the roll bar won't redeploy, just lift up the seat cushion and see if you have parts underneath. They may be wedged behind the back cushion too.

You will need a special two-point bit (I don't know what its called) to re-tighten the cup bolt. Use loc-tite before you re-tighten so it does not come off again.

I have attached photos to help anyone who is looking to make this fix themselves.

SirSwift93

 

Hi Kenth,

Can you help me. I have exactly the same symptoms, - except in my case it happened when my wife was using the car and not my sister !!

Can you let me know if you resolved it ? I'm taking my time on this one and trying to get as much information as I can before I dive in and do something silly and expensive !

Any help would be much appreciated.

Dec.

 

SirSwift,
Thanks for sharing this as I have read many posts in the forums for 208 tops but never found a headrest failure like posted above.
Sounded at first like a beer can or cell phone was caught in it.

The other clue was the bow lock but that would be an electrical short at the RR hatch hinge.

Europe and many other continents refer to an open end wrench as a spanner. In the USA a spanner has two points kind of like the tip of a snap-ring plier attached to an adjustable diameter socket or pliers. Spanner wrenches are used for tightening lock rings that do not have a surface for open ended wrenches. Motorcycles shocks and 4x4 hubs use them as well. If the spring energy is contained, a small punch and small hammer might be suitable for tightening.

Welding is kind of a Band-Aid but it will fix the problem. Welding increases the tensile strength of some metals but the metal will not flex as intended and might break faster than intended. I wouldn't recommend welding on safety related devices.

Thanks, Sirswift

Gator

 

Dec Mc D,

In my case I was able to manually reset everything (following the instructions in the owners manual) and it actually worked again. Good luck.

Kent

 

Thanks KentH for coming back to me.

Tried the procedure as per the owner's manual but to no avail.

I've thrown in the towel I'm afraid and will take it to the local MB dealership on Wednsday for a session on their diagnostic computer.

Thanks again.

Dec.