I have a 2003 dodge ram van. Sometimes headlights won't come on for 10 minutes. After van is started.

There are no relays or electronic controls for the headlights. That being said, either the hi/low switch on the column is no good, or the headlight switch on the dash is no good. The next time it happens try fiddling with each of these switches and see if one in particular makes the lights come on. If one does, that's the bad one.