it is the break light switch attached to the arm on the break pedal one of the wires broke or came off. the switch turns on the break lights and deactivates the lock keeping the transmission in park.
How do you turn on dash lights 1993 mercury grand marquis
where is the fuse for tail lights in 1988 mercury grand marquis
Turn on headlights/parking lights and adjust dimmer control
where you turn on the headlights ... push the button
It is a module under the dash.
dash lights and tail lights cut out
There is a lights control box under your steering wheel.
Bad door switch or bad headlight switch
Mercury Grand Marquis for one and I am sure there are others that I am not familiar with
change the brake lights check the fuse check the brake light swtch
no lights only hige beams if i hold handle up
you need to replace the the keypad on the door....the membrain has cracked and is letting moisture in.....if you leave the headlights on auto you will find they will go on and off too