w220 climate control question
 

my w220 is having climate control gremlins. what does it mean when the EC light is stuck on?

pressing the button has no effect at all. the system seems to have plenty of pressure.

thanks!

probly low on refrigerant..

EC= economy mode, no compressor operation.

On that car 7 MOST newer MB's that can mean almost anything.
The A/C controller doesn't turn the compressor directly. IT sends a signal to another control unit called a SAM (signal activation module) & that module looks at the refrigerant pressure & temp & then turns on the compressor.

To diagnosis a MB scanner is needed to see what command signals are there & what pressure is in the system.

on that car the evaporator temp reg is the most common cause of no compr operation and ec light on.it is in the evap case above the acc pedal and is just a push in with a two pin plug.