Phone [Q] Over Heating

So I am run a few costume roms on my LG e970 but what I noticed that it's overheats a lot now the main reason might be because I leave the brightness on Full all the time but this wasn't an issues when I was running the Stock Android (well other things were but anyway) because in the stock version when my Phone over heated it turned down the Brattiness by default and I was wondering isn't there a function like that in CM11 or PacMan ROM ?