Just installed my D3 in my '04 Silverado with an installation unit I picked up from the local stereo shop. The unit says "GM Class II vehicles with BOSE and Onstar." My vehicle has both.

After installation, everything works great but I have no sound from any of the speakers, including Onstar or the door chime. Not sure if I missed a blue wire somewhere, or if my installation unit is screwed up. Any help would be awesome. Thanks in advance.

connect the blue wire in the gm harness to the blue and white wire on the d3...and you'll have sound. That is that amp turn on wire..get it? ha

I was under the impression the amp turn on, was for an external amplifier.

All of the wires coming out of the GM Harness are currently being used so does this mean splicing into the blue and white wire?