This depends greatly on the year. Check your fuse box, there should be a diagram on the panel telling you what each fuse controls.
Check fuses and bulbs first.
It is on a bracket next to the brake pedal.
under the dash, drivers side in front of the brake.
Some brake light switches are only adjustable once.
How do you stop brake pulsation on 1998 dodge ram
REPLACE THE BULB
Yes a 1987 dodge ram has an e-brake cable
No, all of the fuses are in the fuse boxes.
Possibly blown fuse, bad brake light switch, or blown brake light bulbs.
You have a short to ground in that circuit.
Just connect it to one of the brake lights hot lead, and ground it to the truck.
compare the bulb make sure it is the right number bulb or check inside the sucket and see if the connection are not damage or get a test light to see if there is power comming to the back when the brake is depress