Scotty, I have a 1985 Nissan 720 4x4 Brake light problem. The fuse and bulbs are good but I'm only getting around 3 - 4 volts at any point in the circuit (at fuse, brake pedal switch, and lights). I am fairly convinced this is a corrosion problem, but I'm having trouble locating where the corrosion/problem is. I have many years electronics experience as well, but this is kicking my butt! Any suggestions? Thank you and thanks for the dialectric grease videos as I forgot all about that stuff!
find all the connectors, and unplug them and test the wiring between them. If not failure is found in the wires, remove the connectors and solder the wires together