What is wrong with my taillights on a 95 ford Taurus if I turn on my headlights and the taillights don't come on?

I've had 2 Ford Tauruses, one was a wagon, the other a four-door sedan.

As I recall, the headlights and taillights turn on with the same switch, but they are not on the same fuse in the fuse panel. I'd try checking the light bulbs first, even though it's rare for those to burn out, much less both at the same time. If the bulbs are o.k., check the fuses--- glove compartment on some models; under steering column, left side, small removeable panel on others; some have another fuse box under the hood on the passenger side of the car. If this doesn't work, you might have a broken connection somewhere, or a bad flasher relay, as the taillights are what flashes when you turn on your hazard lights. You might want to make sure your turn signals are working properly and if not, replace your turn-signal relay. If these relatively simple and cheap fixes don't work, you may need an auto tech to run a voltage check on the lighting circuit to find the dead spot in the wiring. Good luck and be careful!