I am the proud owner of a 2001 Maroon SLK320, have fixed several problems on car but recently ran into pse trouble and leaking roof cylinders. Decided to take to dealer and received sticker shock on repairs. dealer wanted $4500 and then didnt know if it would fix problems. promptly took car home and took boot apart and removed pse unit, clean as a pin. took vacuum pump out and using a regular 9 volt radio battery I was able to lock and unlock doors and gas cap & console,just reverse polarity to lock or unlock. Dealer said did not know how to get console unlocked, makes me wonder about any work they wanted to do. I think I can repair all problems for less than $300 for parts. Will let you know if successful.