Problem Description and Possible Solution
The evaporator temperature sensor can fail, causing the AC compressor not to cycle. If the AC compressor does not turn on, the AC system will not blow cold air. If the compressor is stuck on, the air will be very cold at first, before warming up.
Average mileage: 52,500 (52,000–53,000)
6 people reported this problem
I discovered that my AC in my recently purchased 2009 SL 550 was not cooling . I took it to the shop and they determined it was the compressor and evaporator filter or screen. They replaced both and it didn't totally fix the problem. I also had to buy a sensor. That solved the cooling problem. But, my trustworthy, long-time, mechanic also noticed that the Motor Mounts were shot Had to replace them too. Total cost was somewhere around 4,500
Purchased my 2009 SL 550 in Nov 2015 with 49k miles. April at 52k, I had to replace 2 motor mounts, AC compressor , AC sensor, AC low pressure house Total P&L $4,000.00 Great looking car, runs great too But, what's the cost of admiration? I didn't expect these kinds of problems until at least 105k+ Makes you wonder about the new slogan. The Best or Nothing.....really? . What ever happen to the Zenith TV slogan...."The quality goes in Before the name goes on! Com'on Mercedes !