hello XXXXXXXXX
No it's not wired wrong because the harness has connectors on it, however when it was installed they could have pinched a wire or skint a wire that would be touching the dimmer rod when changing from high to low beam.i would recommend taking it to who ever installed the new switch have them recheck it.
Chevy Technician
ASE certified,expired. 30 years experiance self employed semi-retired.