A/C Problem
Thread Starter
Newbie
Joined: Jun 2018
Posts: 3
Likes: 0
2011 GLK350 4MATIC
A/C Problem
When I first turn on my A/C it blows heat. After running the engine for a while and shutting it off, I re-start the car and it will start working properly. While driving, I go through all the controls (on, off, A/C, MAX A/c, Climate Control, etc.) and sometimes it works. It's hit or miss. Could this be a switching problem or is there something else I am missing? I assumed that if it needed a freon charge it would always blow heat but that's not the case. When it works, it's ice cold. I'm perplexed.
Super Member
Joined: Aug 2011
Posts: 861
Likes: 38
From: Philly area
350 GLK, C280
Sounds like the compressor switch is either bad or you are low on Freon to the point where sometimes the pressure is enough in the system to turn on the compressor clutch and sometime not. It also could be a wiring problem in the clutch circuit. When it is not working, open the hood and look at the center of the AC compressor. See if it is turning with the pulley.
