This is just a shot in the dark, but some aftermarket radios have a way to switch their output depending on whether or not it's being used with an amplifier. If it's set to use an amp and you don't have one, there'll be very little or no sound. Is there a mystery switch or button somewhere on the radio?
Nope.
I was told he thinks internal amp is dead. Or something on the board itself.
With no real parts list or schematic of the internals.
It was a shot in the dark.
So nothing ventured....nothing gained.
