Car thinks lights are on, but they are not. Loose switch?

My climate control and radio backlight will dim (as if the lights are turned on) randomly and then come back on bright as usual. Sometimes when I turn the car off I'll get the "lights are on" alarm even if the lights are switched off. Any idea what faulty switch or relay may be causing this?

Ah okay this happens whenever I touch the brake, whether the car is on or not. Door chime turns on, gauge cluster and console lights up, radio and AC lights dim. Weird.....

Fixed it! My brake light was working fine, no failure message or anything. Turns out either the brake light or tail light filament was broken and were touching one another, causing the tail light circuit to receive power whenever the brake was applied, thus triggering a sensor that tells the car the lights are on. Wacky! Never had a bulb partially fail before.

That's pretty interesting. Thanks for reporting. And nice work figuring it out.

LED bulbs FTW