running lights, brakes but no power to trailer from truck

[papermakermd]

I don't leave my battery on my trailer while in storage just back the truck up and plug in. I''m just usually checking inside and need to run a slide out and need a little light.I have done this with my other trailer and with my new Reflection. The last two times there is no power to the slides or interior lights but all exterior things are working. Could this be a fuse or a wiring problem. Leaving on a trip tomorrow and hoping for an answer.

[huntr70]

Battery disconnect is in the correct position?

There is usually a charge line fuse in the block under the hood of the truck also.

Our GMC dealer truck will blow the fuse if used for the landing gear with no battery.

[papermakermd]

Thanks Huntr70 I will try to find the fuse. I never had this problem with my F-150. I have also used this truck before.

[SolarPoweredRV]

I recently experienced something similar on my 2019 F-350.

When I had it checked out by the dealer, they told me that the computer will not send power to the trailer until the computer senses the trailer via resistance from the terminal for the trailer brakes. To get power to the trailer you have to step on the brake pedal and that is when the computer will send power to the trailer.