Cup holders in the dash are known to break requiring repair or replacement.Google+
Car Problem Reports
Mercedes-Benz CLK320 Cup Holders in Dash May Break
Mercedes-Benz CLK320 Problem
Average Mileage: 79,764 mi (52,000 mi - 92,115 mi)
Visitor, 2005 Mercedes-Benz CLK320, 90,000 mi
Cup holder stays out. Can be forced in with a loud pop. Then hard to pull out again. Ratchet probably mis-aligned due to use. Attempting repair - difficult as you have to remove center console to include the part between the seats.
Visitor, 2004 Mercedes-Benz CLK320
4 times it has been replaced under warrant an my CLK320 is a 2004. I am coming out of warranty again and it is broken again. I guess I have hard hands
Visitor, 2005 Mercedes-Benz CLK320, 92,115 mi
Cup holder latch has broken tab, fell out with spring onto floorboard when holder opened.
Visitor, 2005 Mercedes-Benz CLK320, 52,000 mi
Cup holder started jamming and a plastic piece with a metal wire broke off, holder stays open and won't stay closed.