I can still fax you the diagram if you want it, but here's the color codes (these wires are located on a harness that plugs into the factory amp underneath the head unit and behind the NOT AN ASHTRAY pocket
on the SMALLER connector:
line level signals and shieldings are as follows:
Driver: RED/BLU (+) / YEL (-) [B1, B8]
Shield: BRN [B5]
Frt Pass: BLU (+) / RED (-) [B4, B11]
Shield: BRN/YEL [B2]
Left Rear: BLU (+) / PNK (-) [B3, B10]
Shield: GRY/BLU [B9]
Right Rear: LT GRN (+) / PUR (-) [B6, B13]
Shield: GRY [B12]
Remote lead: B7 (YEL/GRN)
The cavity number (Bx) represent the connector viewed FROM THE HARNESS SIDE (not connector side) with B1 being the epper left cavity and B14 beind the lower right one.
Use the shield wires by soldering them to the shield on your RCA cables (you will need to take apart the "upstream" half of your RCA cables to get access to the shielding. Doing this is important as it shorts the factory shielding to the aftermarket shielding. Directional RCA's ground the shield at the AMPLIFIER and float it at the source. This way, any noise picked up by all leads on the RCA length will be referenced to ground at the amplifier and will not get amplified. If you skip this step, you might introduce noise into the system. It is important to get directional RCAs for this to work (or anything with a shield that is grounded at at least one end).
Now, I do not yet know the max unclipped voltage of the factory head unit preamp signal (if you discover it, I would be obliged if you reported it here), so you might benefit from a line driver. I want to find out what the voltage is before buying one, because if it's high enough, it won't be necessary.
BTW, I don't take responsiblity for any errors or omissions in this post... cut-n-splice at your own risk! if anyone finds an error in the text diagram I just copied, please let me know so I can edit this post.
So I read many different forums before I started my installation of my 4 channel amp and I just cut the wire harness apart since I have the wire diagram I connected it to the LOC and ran it to the amp bypassing the factory amp but i can't hear anything