International LT625 headlights stay on all the tine

[Rawze]

Do they shut off with the key switch?...

It might just be the daytime running lights that you are referring to .. and newer trucks are programmed often so that they stay on always, or stay on once you hit the switch one time.

They will also often come on and stay on if the daylight sensor (a small black sensor) in the dash just under the windshield is covered up by someones junk that is laying up there and covering it.. or if the sensor has gone bad.

Prostars are also known to have ghost issues like that if the fuses in the fuse pannlel are tarnished. here is some info on this:
http://rawze.com/forums/showthread.php?t...1#pid12861