I installed an after market system in my 97 XL a couple of months ago.
it worked fine until yesterday.
it is a Jensen 40x4 w/ 400 watt amp and sub.
the 4 speakers quit working but the sub works.
I swaped the deck out with one my daughter had.
it worked fine, wired correctly, not as much volume but sounds clear.
Until I switch from acc to start without turning deck off first,
then it drops the deck side and plays the amp side ( probably because of different power source?
so I turned off truck, turned off deck, restarted truck, turned on deck
and it played fine, for about 10 min.s, then same thing.
could it be the power supply ?
and why would it be intermitant?
also, the newer player is a Panasonic 50 x4 w/ mosfit.
the heat sink gets too hot to touch, Is that normal ?
btw, it does it cold too.
does anyone know what would cause this ? Brad

 

Sounds like one or more of the speakers wired directly to the deck has a wiring problem, or is internaly shorted. That causes the amp in the deck to go into "protect" and shut off. It's possible that a wire has rubbed on some metal, and is only making contact when shook or vibrated just right.

 

I had a similar problem. mine was just a loose wire in my wiring harness.

 

i also think it may be a speaker problem bad voice coil try fading it to one speaker at a time and see if the amp goes into protect mode.