On this car, if the CC is on and the EC button is not selected, the compressor is on. It is variable rate, and can run all of the time. When little cooling is needed, the compressor can run down to <10% capacity.

------------------
Benzmac:
1981 280GE SWB
1987 16V
ASE CERTIFIED MASTER AUTO TECHNICIAN
SERVICE MANAGER FOR 14 BAY FACILITY
MERCEDES SPECIALIST 8 YRS
PARTNER IN MERCEDESSHOP.COM