Hi,
I'm looking for help with the electric closing trunk function on W211 Sedan Lift version.

Issue description:

• After pressing the red button in the trunk lid, trunk starts to close but in a midway stops and returns to a full open position. Same behaviour when closing by a button in a cabin by the driver's door. Please see the attached video. https://streamable.com/3xwg5n

The trunk can be closed with pressing again button in the middle of the way down and with the light push to the top of the lid to helps the movement.
The red close trunk button is lighted. Fuse is good. The cable harness in the trunk is in good condition no cut cables. Springs are new. No problem when opening.

What can be the issue? Is the electric motor old and without the strength after the years to close the lid all the way down? Should I look for new(used) electric motor and just swap the motor? Is there a way how to maybe fill the fluid in an electric motor?

Many thanks for your help.

 

Try normalizing it. Mine does that once in a while. Open and close all the windows/sunroof and hold it for an extra 5 seconds while it's open/closed. Also use the button by the door to open and close it. Also make sure the batteries in your keyfob are good (if you have keyless go). If you walk away while it's in the middle of closing, it will do that. Also make sure that there's nothing in the way, it might think there's something blocking it.

 

Thanks for the hint I just tried it. Main battery was recently replaced and normalization was needed for windows (no roof). Unfortunately normalizing of the trunk did not help.

With closed trunk, I held the open trunk button in the cabin after opening for 4 seconds. But when closing trunk did the described issue even I hold it for additional 4/5seconds but with no results. After few attempts trunk stuck in open position and non-responding to buttons.

Additional info I do not have keyless-go and batteries in keys are new.

 

You could try getting a scanner that scans for MB specific codes and see if there are any error codes and clear them. That always happens when you have low voltage issues with a battery that was replaced.

 

Don't forget to check the electrical harness by the left hinge. A broken wire will have the same effect on opening and closing.

 

The electrical harness is good it was checked in service. This was told me by a mechanic.

Error codes related to low voltage after battery changes was deleted as well in the shop. But I will double-check that.

 

Have you every found the issue ? I know this is old but im trying my luck ! My trunk stops halfway and acts like there is something blocking it. Thanks

 

On my car, I discovered the trunk latch over the license plate was stuck in the "open" position (handle pulled to rear of car). Pushed the handle to "closed" position and all worked normally. This happened to me several times until I got the latch to free up from years of dirt and oxidation.

 

thanks for the answer, how did you get it unstuck? I have the same issue.

 

I just used my fingers to move the handle back. Not much pressure at all. Spraying a bit of lube to the hinges and working handle back and forth helps.