you will probably want to check a few different things ...
pop off the outside light cover and remove the bulb
check to see if it is burnt out or not
check the contact points on the light fixture and the tip of the bulb
(somes they get corroded or rusty over the years)
if that all looks good, go to the next step
some of the campers had a black switch on the light itself, some did not.
some campers have a switch on the outside light, as well as a middle switch inside the camper (if you have this set up) both switches will need to be on
for many years, they put a 2nd switch inside the camper (either on the front of the cabinets or back on the rear wall of the camper near the inside / back door area). This was used so you could turn the outside light off and no kids could walk by and turn your portch light on while you were not around.
If you have 2 switches, just try both a few differents ways to see if the light will come on
If all that fails, try checking the fuse.
The fuse will either be in the cabinets on a small fuse block, or on the older model it was located in a small funky fuse block way up in the front / drivers side of the camper (far front corner, I think they were glass fuses back then -- near or on the carpeted area of the upper step in the camper)
hope this helps
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