So my Missus just recently bought a 94 magna and wanted me to put a cd player in it like every other car she has bought. I have done this a few times and even I'm no where as experienced as some of you guys on here, I think I know what I'm doing.

Long story short, ignition was turned off and head unit was groused and after reading through a few threads on here, all wires were matched up correctly. Before putting it all back together I tested it by turning the ignition on to ACC, head unit came on fine.

My problem is, I now have everything connected and when the key to ACC or ON the head unit doesn't turn on... I noticed that while in ACC the fan switch doesn't work or the interior light either. Had a look at the fuses and noticed the radio and fan switch fuses were blown, replaces them and still doesn't work.

Any of you guys have an idea where I've gone wrong?

You have miss wired up something wrong, hard to say what you have done wrong without looking at the car.