Hello, I recently acquired a 2010 Mazda Demio/2 and I'm running into an issue with the air conditioner. I checked all the fuses and relays, they're all good.Checked power to the compressor and evap fan motor, all good.
The system just wont tun on when activated, the system worked fine I'm told, but stopped working. The system is charged and pressurized.
Any ideas on what I am missing that could be causing this issue? I did notice some corrosion on the ground terminals and clean it up best I could, but will replace the cables.
Also, could anyone tell me what this device on the negative terminal is and its purpose, thanks.

 

Welcome to the forum

 

If the radiator fans (most common this time of year) do not turn on when you use the HVAC system is used many models on various manufactured vehcle will not work. We have 3 current customer vehicles waiting for radiator fan units to be delivered next week.

Because of the personal safety and possible environmental hard you really should seek a service shop that specializes in diagnosing HVAC system issues.

 

I agree with calli on this one. Air con should only be worked on by qualified/certified people. Environmental and safety reasons.
You mention the system is charged and pressurized. Please post the pressure.