Car Stereos: No Sound?, chevy trailblazer, internal amplifier

Question
Hi Brian,

I am trying to install a double din Pioneer AVH-P4100dvd radio in a 07 Chevy Trailblazer that has onstar and no Bose system. I have power to the radio but no sound coming out. What could be the problem???? Thank you!

Answer
Hi,

I apologize for the long delay in answering this question.  I'm guessing you've got your problem figured out by now, but if not, here's what I can tell you:

If your Trailblazer isn't equipped with a Bose audio system, then you shouldn't have a factory amplifier.  That means the speakers are connected directly to the head unit's speaker outputs.  The first thing I'd check is the speaker wire connections at the back of the head unit; make sure you don't have a connection that's uninsulated, or a speaker wire that's gotten pinched behind the head unit chassis.  A single speaker wire that's shorted to a metal part of the dash, or the metal chassis if the head unit, can cause the deck's internal amplifier to shut down, resulting in no sound through any of the speakers.

There are a variety of different adapters made to install an after-market head unit into newer GM vehicles.  Make sure the adapter you're using isn't designed for Bose-equipped vehicles.  If you're using the wrong adapter, that can affect the audio output.

Some adapters come with RCA plugs for the head unit connections, with instructions to cut off the plugs if you don't have a Bose system.  Make sure you're following the directions; in a non-Bose vehicle, you should be using the head unit's speaker outputs, not the RCA outputs.

Hope this helps!

Brian