Yesterday driving on the highway my headlights and all interior lights started dimming and eventually flickering to darkness. My headlights won't go on and interior lights (dash, ac controls, shifter) will not illuminate. Stopped the car for a few minutes got another flicker and they are out completely. Tail lights are also off.. Fuse? High beams work not low beams

 

The tail lights and dash lights get their power from the same fuse, fuse #60 under the hood. From the fuse, the power goes to the tail light relay and then to the light bulbs. For the tail light relay to be energized, the light switch on the steering column is turned on and the light switch sends ground to pins 20 and 58 of the SECU (Smart Entrance Control Unit) and the SECU energizes the relay.

This is all independent of the headlights.

The headlights operate similarly, but a little more complex. 4 fuses, all under the hood, feed 2 relays, one for each headlight. Relays get energized when the headlight switch on the steering column grounds out pins on the SECU module which then energizes the headlight relays.

Common points are the SECU module and the headlight switch. I would check out the headlight switch first. The switch could be bad, but you may have lost the ground connection to the switch.