Where is the condensation supposed to drain (from the car's air conditioning system)? Perhaps the drain is blocked. I'm not finding any water dripping and fear that it may sometimes collect and occassionally begin to stink. I've cleaned the in-cabin (underdash) filter element, and it did not smell. After use of the AC, if the vent-fan is left on, a sublte odor, like old leaves(?) becomes apparent.

Dont know exact location on your model....but Mercedes hides the drain above the sound/heatshield cladding on a lot of models, so you might not be able to see it.........however...with the a/c operating you must get condensate dripping after 10 minutes of operation or there's a problem...only reason not to is if transmission is hot and vapourizing the condensate before it gets to drip on to the floor.


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The drains are located in the rocker panels on both sides..fore and aft.

Take a Q-tip or pipe cleaner and clean the nipples thoroughly...a lot of posters have commented these get clogged with debris and can cause the backup of water causiing a moldy smell. Actually I think these drains are primarily for the sunroof and roof rails, but they might be the cause of your problem..

Keep us posted !!