According to the 2003 Ford Explorer Sport Trac Owner Guide :
In the fuse panel IN the drivers side end of the dash :
( # 13 is a 15 amp fuse for the center high mounted stop lamp and the other
stop lamps / brake lights )
almost out of brake fluid,check this immediately.
The parking brake light stay lit on the 1999 Mitsubishi Montero sport the parking brake is working and you have not put the light off.
Just unscrew the rear brake light, turn out the socket, and replace the bulb.
The left stop is number 3 and the right is number 7. You might check 9 and 13 also they are related to the brake pressure switch. Is that another vehicle sold WITHOUT AN OWNER'S MANUAL??????????
Check your brake fluid level in the brake master cylinder in your engine compartment when it is low your brake warning light will come on
under the dash in the fuse box
Should be located at the upper end of brake pedal under dash area
The fuse panel in the 2002 Ford Explorer Sport - 2 door is on the drivers end of the dash Open the drivers door and look at the drivers end of the dash , you will see a removable plastic cover panel for the fuses
The brake light in your dash will turn on if the brake fluid level is low in your brake master cylinder in your engine compartment
The owners manual shows fuse # 3 - 7.5 amp - for left stop / turn trailer tow connector in the fuse panel on the drivers end of the dash ( the fuse panel cover is visible with the drivers door open )
Brake light switch might need to be replaced. Simpler answer would be a blown fuse.
I have the same problem - but my third brake light slightly flashes when the car is of (Explorer 1998). I have replaced the "stop light" switch with no improvement at all.