2014 TOYOTA hIGHLANDER When you turn on headlights, the A/C lights and clock turn off

Hello, This sounds most like a bad headlight switch. There is nowhere else that changes those settings except the body control module or cabin control module, whichever you have. There is supposed to be a change in brightness, so I assume that portion of the circuit inside the headlamp switch has failed. Test before you replace.