Here's the scoop on this one guys. I tow a 34ft enclosed Haulmark trailer. The question I have is that my Prodigy shows there is a short with the brakes. I have repaired and sealed the areas that were connected with those blue 3M connectors, and thought that fixed the problem. The brakes on the trailer are working when I either hit the brakes in the truck and when I grab the manual lever. I also noticed that there is a thumping like noise that is rythmic coming from each of the wheels. It is more pronounced on the left front tire on the trailer. I am thinking that a wire has rubbed through inside the hub itself. Is it normal for the brakes to make a rythmic noise when plugged into the truck? I am leaning towards it is not normal for them to do that when parked.

 

Older models of the Prodigy (serial numbers below 0130001) had a software problem that caused a false ground/short indication; don't know if that applies to you. The trailer is not moving when you get that thumping noise (it's not normal, moving or not)? Sounds like you may have to pull a hub/drum to see the condition of the brake system.

Steve

 

I have eliminated the controller already by hooking up to a new TT at the RV dealer. The trailer is not moving when I get the thumping.

 

I'd dare say that's not normal......at least on anything I've been hitched to.


Dan

 

Well, It is a Haulmark. Start by throwing it in a ditch. Take the wheels off and put them under a Quality Trailer.


Usually I don't bash stuff but I have a 20' Haulmark that when Brand new Leaked water at the man door. The dealership denied any leak but you could clearly see the water mark on the wall. Then after I started to modify it for Our needs I found bad welds throughout the whole trailer from the Ramp door to the A frame and coupler.

That being said makesure the shoes are good.and the Ground is the biggest concern.

 

Did you actually check and see if the ground between the trailer and the truck is okay? You might get weird stuff like that if it's grounding through the hitch gear. When I test out trailer problems, I always try to do it with the hitch disconnected and only the plug hooked up to a test vehicle so I'll know right off the bat if the ground is crap. You shouldn't have more than a few ohms resistance between the truck frame and the trailer's frame.

Otherwise, yeah, you're going to have to pull the drums and take a peek inside to make sure you don't have a wire chafing in there. Also take a peek at the backing plates and make sure that they put something there to stop the wires from chafing on there.

The last place to look is in the trailer's plug, provided it's not a molded, one-piece cord. You might have a situation where there are only a few strands of wire being asked to carry all the current or worse a few strands might be shorting over to something else inside the plug.

 

My 27' V-nose leaks real bad around the rear ramp. Also had the rear driver side wheel fall off while towing. Needless to say it no longer goes on longer trips, lost the faith and take the 14K goosneck.

 

Jack it up, pull every one of them off, and visually inspect every inch of wire. Test the mechanical movements for any stiffness or binding, rust or missing parts.

Measure the resistance of the magnet coils with a digital ohmeter and compare the readings.

Test the magnets with a twelve volt source, such as a spare battery.

Test the harness from each brake to the hitch with a meter.

Check your grounds with a meter. Rust is not as big an issue as an expert qualified installer who thinks poly-based paint is a good rust preventer - that stuff will instantly seep into a connection (such as a ground) and effectively INSULATE IT ELECTRICALLY.
*Thanks to the diligence and dedication of some dim-bulb at "Georgie-Boy" I had to clean all of the tank sensor connections on a class "A" recently...

Something ought to show...

NOTE: Somewhere in a practical joke section here, I mentioned that if you really want to mess with someone who just did a thorough job of cleaning their battery terminals, all you have to do is spray them with clear polyurethane. INSTANT ZERO VOLTAGE!

- But nothing obvious shows, and the terminals themselves MUST be clean, so...

 

Grey, you are sooooo mean.......you didn't have to tell the world!!!

 

Thanks for all the tips guys. I am thinking that it has to be a wire or a possibly a grounding problem. I forgot to mention earlier that the trailer is maybe about 17 yrs old.

 

Those brakes are usually replaced as an entire assembly from the backing plate out (not including hubs and bearings). Drums are part of the set.

You may be able to get smaller parts. I wouldn't, cheaper in the long run to swap it all.