I got a problem i just got a Pioneer headunit from a friend of mines i had it in the car for a couple of weeks worked fine......then i hit a huge bump and it just shuts off.I've checked all the fuses none blown and even connected the headunit to a battery and it turns on and did that red and yellow wire thing and it works.But when i connect it normally from harness to harness it doesn't work!

What can be the problem here i need music!