99 GMC suburban rear speakers dont work. I recently replaced the AC Delco head

[james g]

unit with pioneer.? Now the rear speakers dont work. I've heard that i might need to bypass the factory amp. if this is the case, how is it done? thanks

 

[Molson02536]

unit with pioneer.? Now the rear speakers dont work. I've heard that i might need to bypass the factory amp. if this is the case, how is it done? thanks

Here is a link that should help you get your wiring in order. http://documents.victorytechnologies.com//documents/product/9539.pdf

If you don't have the Bose system, here is the wire harness color code.

1999 GMC Suburban Car Audio Wiring Guide

Car Radio Battery Constant 12v+ Wire: Orange
Car Radio Accessory Switched 12v+ Wire: Yellow
Car Radio Ground Wire: Black
Car Radio Illumination Wire: Gray
Car Stereo Dimmer Wire: Brown
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: 6 1/2″
Car Audio Front Speakers Location: Doors
Left Front Speaker Positive Wire (+): Tan
Left Front Speaker Negative Wire (-): Gray
Right Front Speaker Positive Wire (+): Light Green
Right Front Speaker Negative Wire (-): Dark Green
Car Audio Rear Speakers Size: 6 1/2″
Car Audio Rear Speakers Location: Rear Doors
Left Rear Speaker Positive Wire (+): Brown
Left Rear Speaker Negative Wire (-): Yellow
Right Rear Speaker Positive Wire (+): Dark Blue
Right Rear Speaker Negative Wire (-): Light Blue

Good luck and hope this helps you get some tunes.

 

[Eubyfied]

Did you figure out the answer to the problem? I have a 98 that has done the same thing.

There are only wires for the front left and right and the rear left and right. My far rear 4x10's work, but not the rear door speakers.

I didn't see our model car in the document the guy referenced....

post here if you figured out the answer....

 

[calvinmonkey]

Hey all, I realize that this thread is quite old by now, but just to get the information out there-
I have a 1999 GMC Yukon SLT (no Bose garbage) and when I put in a Sony headunit, all I had to do to get the factory amp to work was connect the +12v remote lead for "amp" from Sony's harness to the factory amp's remote trigger. I bought a wiring harness that connected to the stock stereo's connector (Metra 70-1858 Radio Wiring Harness For GM 88-05 Harness) and the leads were all labeled. Your aftermarket radio will send juice to the factory amp and both the door speakers and the roof speakers in the back will work. If you want to bypass the amp, in my truck, it's located under the steering wheel and I was way too lazy to mess with it once I found out that the stock amp would drive those speakers alright.