Car Stereos: Problem with my dual xd7500n radio, internal amplifier, stock speakers

Question
Hi I recently installed a Dual XD7500N stereo into my corolla 01, and it powers on fine, looks like it's working fine, but there is no sound out-put. When I turn it to radio mode, I can see the display reacting to the radio, or when I play a cd, the display reacts to that too, I just don't hear any sounds at all coming from the speakers. The speakers work fine and I connected all the wires correctly according to a conversion chart I had. Plus the previous stereo I had in my car before worked good with no problems. So am I missing something when it comes to this dual stereo?

Answer
Hi Charlotte,

It's possible that your new head unit has a defective internal amplifier, but before you replace it, you'll want to check your speaker wires.  This problem can be caused by a shorted speaker wire; for example, if the insulation has come off one of the speaker wire connections behind the head unit, or if a wire has been pinched between the head unit chassis and the metal dash structure, this can cause a short circuit.  When this happens, the Dual head unit's internal amplifier will shut down for protection, and you'll lose sound to all the speakers.

I'd pull the deck and inspect the wires--look for pinched or bare spots, and make sure the connections are all well insulated.  If everything looks good, then it's possible that there's a shorted speaker wire somewhere else in the vehicle; but this is unlikely if you still have all the stock speakers in place.  You can try connecting just one speaker, to see if it works.  If it does, keep connecting the other speakers one at a time, until you find the one that causes the deck's sound to shut off.

Hope this helps!

Brian