When on a highway drive lasting more than 1 hour, my heat and A/C system seems to shut down. The blowers won't work and adjusting the temp. has no effect. Must turn off car, let it sit for a while and restart it. The systems then work, at least for a while. My dealer has not been able to find the problem. Diagnostic tests come up clean. This happens in both heating and cooling seasons. My car now in shop for last 7 days and dealer is still stumped. I told them to keep car until they can find, and fix, the problem.
Anyone else had the same problems with heat & A/C &, if so, were they corrected on 2011 Mercedes-Benz S550
by Jerseymike in Little Falls, NJ on January 07, 2013
2 answers 1 comment
ANSWER by globalhelper on January 07, 2013
poss blower motor resistor
COMMENT by clewa on July 14, 2013
same problem sat in dealer for 6 weeks and was later told silcate in the system and I would need to replace several parts to the tune of 8200.00 please advise
ANSWER by 2012 Mercedes on September 04, 2013
On the S550,2011 and 2012, when it is cold, the heat will not work most of the time unless you put it on "high". The dealer said to take it off of automatic and put it on manual. What in the world? Is this a Mercedes or a Ford? At least on the Ford, the heat works. This has happened on two different year models. The only way you can get any heat is to put the heat on "HI". When you do that, it gets so hot in the vehicle you cannot breathe, and then you have to let it cool off, and start the process again. One of the dealer's solutions was to do as you had to, and turn the car off and restart it. The dealer said he thinks my vehicle is possessed. I took it to him one day, and even though the settings were the same on the driver's side and passenger side, there was heat blowing from one side and AC from the other. I think it is a defect Mercedes is not willing to admit to. Meantime, the rest of us have to suffer with a heating system worse than a junk car.