The brake lights in your 1983 Nissan pickup truck are controlled by the brake light relay switch. When the brake light relay switch malfunctions the brake lights will stop working.
Check the radio/Acc fuse...
try the flasser cam its under the dash
The lights need to be taken out with a screwdriver Phillips usualy
check your fusible link, its connected to your positive battery cable,check for burnt marks or it might be swollen.
Because you have bad lights.
how do you change the tail lights on a 1996 Nissan pick up?
needle might be cracked
Use a volt-meter to measure the voltages and see what you are getting. You might have a couple of broken wires.
hazards and turn signals have separate flashers. replace flasher for turn signals
short to ground or a blown fuse