Heres the deal...the truck has two amps in it. One under the dash that powers the doors, dash, and rear speakers, minus the sub. From there a signal is sent to the amp under the center seat as well as the remote turn on. There is a way to put an after market sub amp in without changing out the rest of the system. In fact you can leave the stock sub amp in place and just remove the stock sub box. Most shops are going to shy away from our systems and will tell you they have to be rewired to do anything. Well most shops don't specialize in researching stock wiring diagrams and they have to make money so the best thing for them to do is charge you for rewiring your system. I spent the time researching our wiring so you don't have to mess with having a shop telling you its gonna cost big bucks to make add on's to our stock systems.
This is where it gets tricky...not really. If you pull the stock head unit out and remove the harness from the radio and the antenna cable you can begin your wiring for your after market sub amp. The stock amp only uses two of the channels off the factory unit. The factory unit is actually sending a high level signal, meaning it will drive a speaker, to the 5 channel amp before it branches out to all the speakers...still following me? From there the 5 channel amp sends a signal to the sub amp under the center seat using outputs out of the 5 channel amp under the dash.
The front speaker outputs off the factory unit are not used and are actually not wired on the harness that plugs into it. Look closely you will see the factory harness is missing four wires or pins. The factory unit feeds the amp using the rears out of the head unit. The four wires you want to look for are as follows:
(ALL THE PINS I REFERENCE ARE ON THE MAIN HARNESS THAT HAS THE MAJORITY OF WIRES COMING OUT OF IT!)
Left Rear positive+ (DG/DB) Dark Green / Dark Brown tracer /PIN#18 on the harness
Left Rear Negative - (DG/OR) Dark Green / Orange tracer / PIN#19 on the harness
Right Rear positive+ (GY/DB) Grey / Dark brown tracer / PIN#20 on the harness
Right Rear negative - (GY/OR) Grey / Orange tracer / PIN #21 on the harness
Those four wires feed the sound to the factory amp that is mounted above the glove box. The factory amp is a pain the arse to get to so don't bother messing with it.
Purchase a PAC SNI-35 or equivalent high level to low level converter. Try to get one that has gain adjustments on it so you can set your output from the head unit to the sub amp. Look to spend about $35.00 for this part. Wire the converter inline with the wires above paying attention to your polarity and balance (Left and Right). While you have the radio out go ahead and tag your ignition wire to the radio to use as a remote turn on for your sub amp. That wire should be pink with yellow tracer (PIN #2). Make sure you add a small 3 amp fuse to the remote turn on lead at the head unit in case it does short out due to installation or whatever. Always use a meter to check to see if its the correct wire. Snake your RCA's and remote turn on from the head unit area to the desired location of your sub amp.
You will have to run your own power wire from the battery to the amp. Follow all the rules of wiring such as a fuse at the battery and using a grommet on the firewall. I was able to snake a 2 four gauge wires through an existing grommet in the fire wall. If you have an auto you can use the block plate for the manual transmission pedal, I know you have an RC but I wrote this so the QC guys can do the same.
Make sure you connect your RCA cables to the converter and tape them up.
You can go ahead and unplug the stock sub amp under the center seat so that it does not power up. Just unplug it by removing the stock harness from the amp.
I mounted my sub amp under the driver seat and placed the sub box behind the passenger seat. The stock speakers that run off the stock 5 channel amp are OK and will probably need to be replaced in the near future and can be without having to mess with changing out the amp. Thats a whole other write up.
I have all the schematics for the wiring in an 05 and have spent many hours studying the wiring for the stock setup. Even though I have listed wires on here always double check and test if needed. I won't be held responsible if you tag the wrong wire.
If you have any questions beyond what I have provided hit me up via PM and I will be more than happy to help a fellow 10er get er done. Cheers and good luck!
:rock:
P.S. please respond to this thread if it worked for you. Again this is only for the 05 RC's and QC's . I assume the 04's are the same, but you may want to double check. I know the 06's use a completely different setup and since I don't own an 06 well.....your on your own.
The stock sub and box are major poo and I tried many after market subs in the box to see what sounded best and had no good results after 3 speakers. Your best bet is to get an after market box with an after market sub.
