I don't post alot but I read through here all the time and I absolutly cannot find any topics that address this issue all the way. I am in the middle of a system install and I am completly done except for addressing the issue of audo input into the amp. I have a 04 with a stock HU using a amp that supports high level inputs. I have the speaker wire to rca adapter and I am taping into the rear speaker wires (pinouts 15,16 5, 6, according to manual) and im getting nothing. I have confirmed using other audio sources that everything else is connected correctly and functional. My issue is isolated to the stock HU and this adapter or its wiring. I am reading .1 voltage from these wires with the radio on and all channels balanced to center at a decent volume level. I understand that this is not the recomended setup. Can anyone confirm that in a 04 these rear speaker outputs are working and if so can anyone confirm the colors of these wires or if these pinouts are correct. seems like these topics always have one of two outcomes either it gets resolved with no info about wire colors ect or they get told to get a aftermarket HU. just doesnt seem to be enough ap2 posts in here that dont involve using the lucid panel.

 

those are the correct pins, and headunits from all years have outputs
on those pins even though early cars had no pins/wires in the car's
harness that connected to the headunit's rear channels.
when you say "balanced to center" you mean both the Left/Right balance
centered and the Front/Rear fader centered?
when you measure the voltage, are you measuring the speaker wires or
the rca adapter output? make sure you are measuring AC voltage,
not DC.

 

When measuring for voltage I have tried at both the rca adapter and the wires before I made the connections. Right now I have isolated my troubleshooting to just the right channel which is pinouts 5, 15 red/yel for pos and brn/wht for neg. When I say balanced to center you are correct I have both the fade and balance on center however I also tried fading to rear. For testing I'm gonna need to step out and get some supplies because these wires are short with not much slack to work with right now. I have a few concerns with my setup and maybe this is the problem. I figure these wires are running to the back somewhere so I basically just butt connected into the wires leading to the HU harness and left the rest (going through to the back possibly) disconnected. I have yet to try tieing them all in together because there is little room to work here and didnt think this to be necessary. Is this possibly my problem? I was pretty confident with having the pinouts available that I would get this one right the first time so I used butt connects and cut the harness to do so. If for some reason I cannot get these rear channel speakers working I was thinking of using those connects that just clip onto the wires and do not require cutting and just hooking up to the front channels. Would this degrade this setup further?

 

behind the driver seat - remove the 2 screws,pegs holding the little panel on, and pop it off, you should see the factory wires on a split loom right there, you can double check your wire colors there.

 

Ok this is embarrassing but heres the deal. I actually had this hooked up correctly all along however the volume is so low to the rear inputs that it is not audible or even something you can feel on the speaker. I realized this was working after taking a tiny computer speaker and hooking it up to verify sound. This amp is 250watt when bridged and its hooked up to a jl 10w3 in a stealthbox. It appears to be bridged properly and settings are correct but sound is only audible at full volume full fade to the rear and full gain on the amp so something is wrong. I didnt want to test long in these conditions but I also noticed that it was much louder with only 1 rca connected (found by accident and know this is generally not safe to run long) so now I have a seperate set of issues. I'm hoping that this is maybe a poor ground and not something more serious. I believe im running both 8g power and ground and currently grounding into one of the bolts on the rear strut bar like in darkknights wiring guide. I did not sand this down which is probably what i will try soon as im off the computer. Other than checking grounds does anyone have any suggestions for troubleshooting this problem? You guys are great btw so much knowledge to be found here.

 

You say you have an amp that supports high level inputs, but if you are using RCA's, do you have a hi/low input switch? Most of the time when you use RCA's, the RCA's are on the low level input.

 

buy an aftermarket head unit , it is a lot better.