New member here, Hi All! My 2000 Grand Marquis LS dome /floor/auto headlights (when selected) turn on randomly throughout the night when car is off... I replaced the LCM after hearing reports of this problem being related to those. I just saw the dome light on last night... already cost me a battery. Maybe a bad headlight switch? How difficult is it to change one? It acts the same as when I unlock the doors with the fob. (But the problem is present with doors locked or unlocked) Weird. Anyone been there with this?

 

You should check the keyless entry on the drivers side door. It has been known to leak and once water gets under the keypad and on the circuit board it can cause a short. Basically the car acts like someone has come up and pushed one of the keys on the keypad. It's pretty easy to fix.