one brake light works other does not-not bulb
test the ground there at the light----take a look at your chassis ground for corrosion...undo the end of the black cable...wirebrush "frame" and lug, to assure solid ground potential~
Do as judge stated. Also check for voltage at light socket. If both voltage and ground are present inspect socket for corrosion. Clean posts in socket and re install light bulb. Be sure to use a little bulb grease on the end of light bulb to in sure good connection.
There should be a junction box under the vehicle by the spare tire. It will have the root cable coming from the front then it will branch out to each side and out to the trailer hitch if factory equiped. Check this connections if the above fails. Clean them and use dielectric grease to seal them from moisture. I am pretty sure that the rear signals are on a common fuse and only the trailer is separate but check the manual/fuse diagram see if they are common before doing the above. Avoid dirt in the eye if possible.
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