Hey there,
Drove Crossfire to store yesterday. When I came out the remote for the alarm did not work. I put the key in the door then opened it to the sound of the alarm. Put the key in the ignition and that did not help the alarm was still going off. Car would not start.
Towed to my friend’s Mercedes shop.
A bit later he informed me the PSE pump was bad, no idea I even had one?
PSE pump also know as the Door Vacuum Pump, located in the trunk.

Part #1708000848
Here is a picture and more information on that part.

<http://www.benzworld.org/forums/r170-slk-class/1600468-pse-help-needed-1708000548-compatible-1708000848-a.html>


Does not seem too expensive or difficult to replace.

Hope this helps someone.


Cheers

Pete