Hmm, almost sounds like the light controller has been programmed for daytime running lights, but seeing as you've only just replaced the switch, then logic suggests there is either a fault in the switch itself (electrically, or the new one is "wired" for DRL), or you have managed to plug wires incorrectly/shorted something out.

Do the headlight stalk functions (high or low beam, flash on low beam) work normally ? That might give you some clues.