Air condtioner problem

[fabiancampos08]

Whenever I use my air conditioner, I can only use levels 1,2, and 3 but whenever I try to use level 4 the fans just shut down, regardless if its cool air or warm. Is this a common problem? The car has been like this since I bought it last year. I dont know if this has to do with anything but, I know the prior owner of my car did a ka to ka swap. so I dont know if it was itstalled incorrectly or if its simply broken. what do you guys recomend me to do?

help me plz, the days are getting hotter and hotter.