99 Sierra No Sound From Radio

[crazylarry]

Hey guys I just discovered your site & I hope you can help

It is embarassing to ask for help with this as I actually work in the assembly plant where my truck was assembled & have had no luck finding help.

Here goes: A while ago I started having no sound (intermittantly it would work) from the factory radio/cd player.

All displays are normal but no sound.

 

I figured I had a bad radio & would get around to changing it with a spare one(new) I had....Didn't work.

Checked all fuses...OK

Tested for power at deck harness....OK

Disconnected battery to reset possible stuck security dohicky...no change

(I was told this might work as the security,door chimes etc run through the radio.)

I am wondering if I have a problem with a module of some kind but don't know where to start.

Any ideas?

Thanks in advance for your help...Larry