Tow dolly lights not coming on

[aydodster]

A vexing issue with my master-tow tow dolly. When I hooked it to the Class C Sunseeker I get no lights on the dolly. When I take the four prong wire off the Round plug Adapter and hook it to my truck they work. Seems the adapter that connects to the round plug on the RV might be bad or could it be something else? Anyone out there have this adapter go bad? Seems to be to be too simple an answer but one never knows. Thanks Patrick

[ResQfrog]

Check for the fuses in the body distribution box. There should be separate fuses for the plug in at the rear of the coach. This allows the fuse to go bad for the trailer or dolly and not take out the coach tail lights. There will also be a relay and fuse for trailer brakes. If you have a dolly with electric brakes. I believe on the Ford cutaway it is under the hood.

[Oaklevel]

X2
Check with a 12V tester but there is probably a fuse to the tow light plug.

[Ford Idaho]

I'd run a continuity test on the adapter to eliminate it.

Then a power test on the Sunseekers plug.

[RSchleder]

I always have a spray can of "electrical contact cleaner" (plastic safe) with me for just the kind of problem you're having. 12V systems need clean contacts without any contamination to disrupt the current flow. I can't possibly tell you how many times in my 30+ years of camping where the lights on a trailer or a towed vehicle didn't work and a liberal spray of this cleaner on both the male and the female connectors fixed the issue. Simple fix, try it!!!

[Det107]

After all that, check the ground wires, on a 12V system if it's not a short it's always a ground RV, Boat or truck..

[aydodster]

Must have put brain in park and thanks for the reminder to check the fuse box. 20Amp fuse was blown and should fix the problem. Appreciate the timely reminders from the community. Patrick

[Ford Idaho]

Originally Posted by aydodster

Must have put brain in park and thanks for the reminder to check the fuse box. 20Amp fuse was blown and should fix the problem. Appreciate the timely reminders from the community. Patrick

Real glad it was an easy fix and Thank You for posting the fix as it might help someone else.