I installed 2 kicker comp 12s on a fosgate 400.4 4-channell amp. As soon as re-connected the positve battery terminal(which had not come off for at least 4 months) the head unit would not turn on. After taking it back off and trying it again, it came on. Things worked fine for a few hours, then suddenly the head unit would not switch to cd function. Disconnect the terminal to reset and it fixed itself. 20 minutes later, same problem. Well reseting didnt work so I just dealt with it. Now while playing with the FIE setting on the pioneer head unit, the subs went out. I know the amp is getting power, Ive got a nice alternator whir to back that up So if the amp has power and its grounded fine and the turn on lead is connected and no fuses are blown, this tells me that the head unit is just a peice of **** and isnt sending the signal to the amp. It still wont play cds either. Its a pioneer, bout a year old maybe year and a half. Anything else it could be? I want to eliminate any other problems before I just go buy a new unit I currently cant afford. tia

 

My pioneer had a sub on/off setting as well as the FIE. If you have that make sure its on. I've known a lot of pioneer products to have some stupid problems like that, mine had one channel give distortion all of a sudden. i had to get it repaired. I would try reseting the headunit and starting from scratch first.

 

its a lower model, like the $150 variety so there is no on/off..after playing with the FIE it just died, ive taken it off the battery and pulled it from the dash to inspect it and that didnt help much, are pioneers known for this type of malfunction?