how do u reset the air cond. button on the contoller because it doesnt work. on 2001 Mercedes-Benz E55 AMG

the compressor light is lit which means the ac compressor is off but i hit the button and it doesnt start the compressor. How do I start the commpessor so the ac can work?

Asked by for the 2001 Mercedes-Benz E55 AMG
The ec button is on, due to the system having codes, need to have local specialty shop scan and erase system codes or repair, cause of codes.