Audio Systems: muted speakers, amplifier output, rca outputs

Question
i have a 2007 chevy silverado with on star. i have an aftermarket headuint, the onstar wiring harness, a amp and sub woofers. i installed the cd player, the chimes work, the head unit comes on the cd will even begain to play but there is no sound at all coming from the speakers

Answer
Without knowing the make/model of the aftermarket head unit it is impossible to know if you have it wired correctly. Generally, you must have a special wiring harness that is specific to your vehicle and then connect the wires to your audio system.

So, what you must do is first check out the wiring to make sure the amplifier output of each channel is connected to its speaker and nothing else.  Then you must make sure the amps are getting power and the audio signal is getting through to the amps.

The power amps should have two 12v lines connected: One for constant power, the other is for remote turn on from the head unit.

The audio outputs from your head unit should have rca outputs that feed to the audio inputs of your amps.  If there are no audio outputs on the back of the headunit you will need a hi-lo adapter (from places like www.installer.com).

Maybe these generalities will get you going; if not, come back with more specific questions.
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