I have a 1989 Grand Marquis and the brake lights will not work. They used to get stuck on and I would have to remove the fuse to get them to turn off. I have heard the problem may be in the pedal.
The brake light switch is at the pedal, here's a pic of what it looks like
Replace the stoplight switch and it should solve your problem. It's mounted on the steering column under the dashboard and looks just like the photo above. It's just a plunger type switch that goes in and out when you push down on the brake pedal. Very easy to change out. Good Luck, Kenny/MrBlueOval
Sometimes the wires can frey and break right next to the spade lugs. I crimped on a more flexable wire with terminal onto the old ones. Problem solved.
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