2001 Ford Ranger all lights work but brake lights, brake light on back of cab works.
Have you checked the bulbs? Put a new one in just to be sure? If its not the bulb your gonna have to trace down a wire issue, since you said the 3rd brake light on the cab works. That mean fuses and the switch on the pedal are working.
blubs all work, where do you started traceing the wire from
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