So last year I was able to buy an Activator brake controler for cheap through my work.

Now I am supposed to leave Saturday and I plug the fifth wheel in to the truck and I hear like a groan, then a circuit breaker starts cutting in then cooling then coming back on then cutting out again, it appears the brakes are being powered up, yet there is no red light on the controller till I push the pedal, this unit ran perfect last summer, now everything including the truck has sat since then.
Is there something I should be looking for?
To me it is getting power from somewhere and putting on I assume the brakes, as the noise appears to be the brakes.
I find it odd that now it would act up.
Any ideas?

Is there a "gain" adjustment on the control?
If there is and it's set at max it could activate the brakes.
Milt

If the truck and trailer have been setting that long, how are your batteries?

I would first make sure the tab on the plug is in the righ orintaion place so nothing is crossed up. Next thing would be look at all ground points. 99% of the time if your unit has been sitting corrision will build up. Remove all ground points and clean them. Next thing, replace the contoller.
If you hear a breaker heating up and cutting out I would not keep it hooked up until you determine the problem. JMHO

David

Pouring rain here, so did not get to look at it tonight.
Have to work on it in the open.
But my batteries on the truck are optimas, and seem to be good, usualy throw a charge on to keep them up while stored.
Trailer group 24 was new last year, kept it in the garage and kept it on a maintain trickle.
My truck did get broken into a month ago, but I can not see any damage that would affect the brakes, as I say not connected the controler light goes on when brake pedal pressed, and it seems to be just like it was last year, but as soon as I plug in the trailer cord I get the sound and the breaker goes.
I am wondering if I might have hooked up the wires to the trailer battery wrong, but I put white to the ground, and the three other black wires to the positive terminal.
I know one is the propane detector, and one I believe is the water pump.
I would imagine the other is for the lights, maybe.
But I will have to look at a few things tomorrow I hope.

Well, I found the problem, at least it seems to be fine now.

I installed the wires wrong when I reinstalled the battery into the fifth wheel.
It seems unlike automotive the white is ground, which I did have on the negative terminal, But I only put one black wire on the positive terminal, but that one I could see was a red and the black section was a fuse holder they spliced in so that was good.

BUT, the other two black wires, I put on the negative terminals, and that is where I seem to have gone wrong, the black is hot on a Trailer.
OOps, how can you tell I am a first timer?

Yeah, when I saw your 2nd to last post that didn't sound right.

I'd go test the fridge, water heater, converter, brake controller, and everything else electronic before you head out.

Well just got back from a week away, everything worked fine, so my little mix up does not seem to have caused any lasting effects.
Got lucky.