If its just the compressor that's not starting then it could be
bad contactor
bad capacitor
burnt or broken wire
bad compressor
lower than normal line voltage
If you are not comfortable testing or working with electricity then don't attempt this on your own
air conditioning compressor
The AC compressor capacitor in an air conditioning system helps to start the compressor motor and keep it running smoothly by providing an extra electrical boost when needed.
The air conditioning compressor fuse can be found in the fuse box. The air conditioning compressor fuse is actually a relay switch.
To service a stuck Hermetic compressor,repair the start components of the air conditioning compressors.
If the temperature is below freezing outside, there is no need to run the air conditioning. The heater does not use the same set up as the air conditioning. This may be a built in feature of the car so the compressor does not completely freeze up. As air conditioning is running, freon passes through the compressor, making it quite cold internally.
Remove the air conditioning hoses from your 1997 Chevy Malibu air conditioning compressor. Remove the compressor belt. Remove the compressor retaining bolts. Reverse the process to install your new air conditioning compressor.
Remove the belt from your Mercedes-Benz 240 air conditioning compressor. Remove the air conditioning hoses. Remove the compressor retaining bolts. Reverse the process to install your new air conditioning compressor.
The air conditioning compressor contactor controls the flow of electricity to the compressor unit, allowing it to turn on and off as needed to regulate the temperature in the air conditioning system.
The compressor fan in an air conditioning system helps to cool down the refrigerant gas by compressing it, which increases its pressure and temperature. This allows the refrigerant to release heat outside the system, making the air inside the building cooler.
DISCONECT THE BATTERIE CABLE FOR 10 MINUTES ,AFTER YOU RECONNECT THE BATTERI YOU CAN CHARGE THE AC. COMPRESSOR
Low refrigerant causing compressor not to start?
An air conditioning compressor kit typically includes the compressor itself, mounting brackets, bolts, gaskets, and sometimes refrigerant oil.