Rick:
Check the lamp wiring in the trunk and also see if all the side markers are illuminated. As Bill noted it sounds like you have a wire that is shorting to ground. Often a side marker wire will get loose and you won't notice the lamp not being on. The wire can get trapped against sheet metal and create a short. Often the resistance in the various connectors is enough to prevent wires from burning, but the headlamp switch becomes an expensive fuse.
Good luck and let us know what you find
Kelvin Dodd
Global Sourcing Engineer
Moss Motors, Ltd.
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