"Take Key" message
 

My '96 E300D has had this problem since before I bought it, and I think I'd like to finally fix this. Basically the ignition doesn't recognize when the key is out and regardless of whether the key is in or out any time the driver's door opens with the engine off I get the "Take Key" message along with the beeping. This, like any other warning, can be temporarily reset with the R button, but of course I shouldn't have to do that. The local dealer told me it's some chip behind the ignition module that needs to be replaced but I didn't see such a thing when I took a look. Does anyone have experience with this or do I really need to have the stealer take care of this problem?

You may have to take it to the stealer to get it fixed. Its an electronic gadget such as a sensor or chip mounted near the ignition that isnt working

Actually I said it incorrectly. I looked at the old diagnosis from the dealer and they said the wires were fine and the car just needs a new ignition. Today I spent a few hours on this. I couldn't figure out how to remove the ignition so I decided to unplug it, disassemble the connector and figure out which wire sends the Take Key message. I got lucky and it was the first wire I tried, the pink one with the blue stripe. I just reassembled the connector without this wire, reconnected the ignition and all is good now. No more Take Key message, ever. I know this is kind of a hack rather than a fix, but I generally find the beeping annoying even on cars where it works properly so this will work for me.