Start by checking each of the lamps. Make sure they match the socket. That is some have two pins on bottom and some have a single pin. If a single pin is installed in a two pin socket, it will short out.
Next check the wiring. Find the incoming hot wire. It should be jumpered between the two switches. The other side of the switch should go to the corresponding lamp.
My first thought is wrong lamp!
Bud
USAF Retired
Pace Arrow
2003 Chev Ice Road Tracker