Need Info on factory Amp

[NoRockUnturned]

I have a 97 Explorer. I just put a new Head Unit in, and speakers in the doors. When I was putting the wiring harness on I matched color to color and capped off the non useable wires. When I went to turn it on after it was wired I didn't get any sound. After some quick deduction and a look at the wiring harness diagram I noticed that the factory head unit was wired to an amp somewhere. Once I connected the amp wire to the hot I got sound. My question now is where is that amp located? Id like to replace it as well as add a sub in the near future.

Any help would be appreciated.

P.S. I don't think I have the premium sound package.

 

[Gatorblazer]

http://www.explorerforum.com/forums/showthread.php?t=155516

same prob here. amp is located behind the jack

 

[NoRockUnturned]

is that the electrical box where the code to my door is taped on?
when I pulled the plug out of that box to view the wires my alarm went off.

 

[Mbrooks420]

No, the amp is on the opposite side as the computer with the door code on it. You can either bypass the amp, and run the speakers off the power of the new HU, or you can run new +,-, remote and rca's and add another amp. None of the factory wiring is up to the task.