Car radio(Ford Taurus)?

There's really 2 fuses you can check. The one in the car's fuse box for the radio (it's probably tied into other electronics in the dash - refer to your owners manual) and the one in the back of the radio. Yes, the radio will have to be pulled out to check this one.

If both of those are OK, check the wiring to the radio to ensure a wire didn't pop free. If the harness looks OK, you might have just had the radio die on you.

Good luck!

How's your speedometer working?

The constant power source in the radio harness is a shared circuit with the speedometer in many Taurus'. It's a 5-amp fuse in the fuse box under the driver's dash. After-market head units often overload this circuit. You can replace the fuse, but I always like to switch the constant power wire behind the deck to a different source with more current capacity. The cigarette lighter harness runs through the radio cavity, and it's a constant power source with a 15-amp capacity.

(If you have an older Taurus, pre-1996, check your under-hood fuse box instead).

They just don't last forever. If you've gotten 3 or 4 years out of it, that's about average for the aftermarket stereos. If you did better than that, you were already on borrowed time.

Good news is it will be very easy to upgrade to a new stereo. Time for a trip to best buy for a CD player.