QUESTION: If recirc is engaged, but engine is turned off, does system disengage recirc? If so, there is no way to leave it on while it goes through car wash, except those that you drive through.
Used an automatic car wash on my 2010 for first time last week. It was the type where a conveyor pulls it through the wash and the attendants hand dry it. Been using this place for long time without any problems. I always hand washed and waxed it myself before, but cannot do that now.
It came out looking great.
Worst part was trying to explain to person driving it to conveyor about the need to press the Recirculation button in before turning off the engine. Actually I just left it running and she drove it to end of conveyor and turned engine off. She did know how to operate the shifter from experience.
Per manual, if recirc not engaged during auto car washes, water may get into ventilation system. When I hand washed it, I always engaged recirc.
I have turned recirc on and then turned car off and on and recirc was off.

 

ive never heard of this, i never turn it on when washing my car, no problems whatsoever.

 

The manual for my 2012 says to make sure the system is switched off. I would have never thought to do that. Thanks, El Cid!

 

My manual says to "activate the air recirculation mode" when using automatic car washes.
I think it relates to the tremendous amount of water under high pressure coming straight down onto the vehicle at the air intakes for the ventilation system.

 

This is something to look into. I always go thru an automatic wash but never turned the re-circulation on. One time had water dripping in the foot well on passenger side after wash.

Will try to remember to use re-circulation from now on.

 

Hm, interesting read. Thanks for sharing. I'll have to do the same since I do both depending on the weather.

 

The 2011 E Class Operator's Manual says, for an automatic car wash, to switch the heating/ventilation system to Off.

 

Same here on my 2010. There may have been a redesign for 2011?

Thanks for posting this info.