Well, after a lot of searching for the Bose Nav/DVD/Rear Ent wiring diagram, I finally found the only useable signal for adding a sub amp. The issue I had was that tapping the speaker wires on the Bose system changed the impedence too much and threw the Bose amp into a state of confusion. The only logical reasoning behind this is that Bose uses an auto-clip-sensning system that basically tells the amp how much stress the speaker is under through the language of impedence. Notice how when you rotate your volume knob all the way up, it just magically knows when to stop? I realized also that adding an amp for mids and highs would have to be done by grabbing the low level signal before the Bose amp FYI.
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The center console subwoofer is practically located under the dash. After learning that the Bose amp was in the center console at the rear under the storage area, I figured there must be high level sub signal traveling through the center console.
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Sure enough, I popped out the very easily accessible storage tray and spied a 4-wire harness. You might be thinking only 1 pair of wires go to a sub. Well, as I learned when adding an amp to my CTS w/ Bose, they like to run 2 pairs, one for each voice coil. All you have to do is tap each pair and run to a line-level adapter or hi-lo converter as some of you know them by. The wiring is as follows:

***These colors are on the amp side of the plug. The sub side has different colors all together.***

Voice Coil #1 aka Channel 1
+Dark Blue w/ White Stripe
- Light Green w/ Black Stripe
Voice Coil #2 aka Channel 2
+Dark Green
-Light Blue w/ Black Stripe


***THESE ARE SUB LEVELS NOT FULL RANGE..TAPPING THESE WIRES ARE ONLY FOR INSTALLING SUBS***

**Since it is easier to tap the larger gauge wires on the sub side of the harness, just use the plug's corresponding letters (ABCD) to match the wires up.**
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There is plenty of room under most second row seating for one large amp or multiple smaller amps. Even the factory beauty board can be cut to easily flush amps in and hide wiring.

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The 12Volt Main and 12Volt Accessory/Ignition wire locations are pictured below.

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I am a professional installer who works out of Southern California and would love to help out if anyone needs.

760-773-8728 Travis Brown
socaliguy81@yahoo.com

How about us pickup guys is it much the same??? 2007 NBS

I honestly couldn't tell you man, sorry.

The pickup uses the same amp and sub.

yep....as long as you have the same interior, the install should be exactly the same

I read your instructions on tapping a Chevy BOSE amp for adding a sub from back in April. I have an '05 Suburban with the touch-screen factory nav and sound system. I have the sub woofer in the front of the center console. Do you know where the amp is located in this model? Is it best to tap the wires before or after the amp? Your review said before. I'm also going to need some more instructions on which wires I need to tap to get a feed for my extra amp and sub. Thanks in advance for your help!