David Schmalzer

Weird thing. If I have the vehicle running in park, press down the brake and then release, the hatch opens. Is this a feature or something wrong? Any idea how to fix?

Maj. Dundee

I can almost guarantee that you have water entry in the spare tire compartment where the rear SAM is stored. Remove everything in the spare tire area and you will see that there is water corrosion on the rear SAM connectors and also the tail lamps themselves.

The water entry is cause by defective Tail Lamp Seals which must be replaced to insure no future entry. The rear SAM controls both tail lamps activation (stepping on brake pedal) and the opening and closing of the tailgate (read green highlighted).

https://mbworld.org/forums/m-class-w...ml#post7589044

David Schmalzer

Thank you so much! I will have a look when I have a chance. One thing I hate about daylight savings time is when it ends so it gets dark too soon in the evening.

David Schmalzer

I cannot find any instructions online as to how to remove the SAM control unit, can you help?

lkchris

See startekinfo.com

David Schmalzer

Ok, removed the rear SAM unit. there was corrosion, cleaned it as best I could with contact cleaner, looked ok. Applied silicone sealant to the gasket of the right tail light to hopefully prevent any future leaks.
Cleaned out sunroof drains as well in case water was getting in that way. So, re-connected the control unit and so far so good, we'll see what happens after the next rainfall. Thanks to everyone.