Hey all, i got a big problem here . got back to my car this afternoon and found out that my entire head unit stopped working (aircon/radio/etc). however, it still dims along with the rest of the displays, so i don't think its got to do with the power. this happened once in the past, but i just banged it once and it started working again . i took apart the dash and looked over the head unit and there doesn't seem to be anything wrong with connecting wires. is it a problem with the head unit itself? i haven't heard of anyone's hu just going out like this before.

Any feedback would be appreciated, otherwise its another trip to the dealer (and as usual they'll find good excuses to charge me extra or void my warranty by saying i have a sub installed and etc)