My driver side break light went out, so I replaced it (not the first time doing so). I pulled the whole tail light out to do so because the bulbs are a bitch to get in and out. Swapped the bulb and then plugged all the connections back together.

Now, every time I press on the brake my dash/head unit/etc. all light up. For some reason the car thinks that the headlights are turned on and everything lights up.

I know I properly rewired everything and have checked multiple times, what would be causing this?

 

Any ideas?

 

Bump. Nothing?

 

Bad bulb. If the two filaments are shorted together, the brake lamp circuit backfeeds the illumination (parking light) circuit. (I keep one of these in my box to screw with the new guys)

That's the most likely scenario, anyway; it could also be a wiring issue that you exposed when moving the tail lamp around.