amp bypass and premium sub

[zephead99]

Im looking at replacing the head unit in my 96 limited with the JBL system. If i bypass the factory amp, will i not be able to use the factory sub installed? Im not sure exactlly how that sub connects to the system. Is it powered by the factory amp, or does it take pre-amp outs from the head unit to a separate amp in the side panel next to the sub?

 

[wvsquirrel]

If you bypass the factory amp then the sub is useless (unless you reconnect it to an aftermarket amp). I've never seen an OEM headunit with RCA pre-outs before.

I'm not 100% familiar with the JBL premium system (as in how many OEM amps there are), but Ford seems to daisy chain all their amps if there is more then 1. So it's a pretty safe assumption to figure if you bypass any amp, the speakers/subs after it would be useless.