Generally that's due to a bad ground wire but I'm not familiar with the wiring on your vehicle. With a bad ground, current goes through one bulb, then it has to go through another one, usually on the other side of the car, to complete the circuit. Unplug one of the bulbs. If the other one goes out, check the ground wires.
Wednesday, October 17th, 2012 AT 7:14 AM