I have had my F90 running for 4 months now through the stock wires, stock speakers, etc. Just using deck power, no external amps.

Tonight I added a sub amp and a sub, I hooked up the sub pre-out and the sub just sits there like a bump on a log... no bass. The amp turns on so it is getting power and remote turn on signal but it is not moving my sub.

I THINK this is one of those units that you cannot use the internal amp to power fronts, rears AND use the pre-out to run the sub.... please verify.

Also of note... There is a bose sub in the car that I will eventually disconnect, I am not sure if the internal amp (on the Pioneer) has a channel for subs and I need to cut that before the rca will work or not. For right now I am just trying to get the add on stuff to work, then I will go in and cut the wires from the metra harness to disconnect the bose amps.

there is no suce thing as a unit that will not let you use the internal amp AND the PRE-OUTS, the pre outs should have signal from them all the time, go into your settings and make sure that it is turned on

and the bose system is independent from the AVIC, meaning that it doesn't matter what you have done to the factory sub, the outputs should be working fine, some models have a tiny fuse internally on the preouts to protect them, yours may be blown.

i would subtitute something for the source signal to see if the problem is with the head unit or something else, get a ipod (or mp3 player) and a 3.5mm to RCA cable and plug it directly into the amp, and see if you now get any sound, if not then the problem is either with the amp or sub

I borrowed a multi meter and discovered that there is no signal coming from any of the RCA cables (not just the sub), so that shows me what the problem is.

Either that fuse is blown inside the unit, which basically means the head unit is shot (from what I read).

or the RCA cables got unplugged somehow during/after installation.

I will pull my dash apart tonight and attack it with my multi meter to find the truth. Thanks.

I borrowed a multi meter and discovered that there is no signal coming from any of the RCA cables (not just the sub), so that shows me what the problem is.

Either that fuse is blown inside the unit, which basically means the head unit is shot (from what I read).

or the RCA cables got unplugged somehow during/after installation.

I will pull my dash apart tonight and attack it with my multi meter to find the truth. Thanks.

well the fuse inside can be replaced if you send it in to pioneer to be repaired, also 1 more option that could be the problem is that the rca cables are just bad

Have you gone into your settings and made sure the sub out is turned on.

Have you gone into your settings and made sure the sub out is turned on.

that was covered in the first sentence

... go into your settings and make sure that it is turned on