Elec. brakes work intermittently

[tinkerreknit]

My 7-way TT connector works fine at the truck, and with no TT hooked up, my truck's brake controller lights up as it should whenever I use the truck's brakes or whenever I manually apply TT brakes with the controller. But when I am hooked up, the light will only come on sometimes - so I only intermittently have TT brakes. There doesn't seem to be any pattern as to when the TT brakes are working. What are the most likely problems?

[tinkerreknit]

My 7-way TT connector works fine at the truck, and with no TT hooked up, my truck's brake controller lights up as it should whenever I use the truck's brakes or whenever I manually apply TT brakes with the controller. But when I am hooked up, the light will only come on sometimes - so I only intermittently have TT brakes. There doesn't seem to be any pattern as to when the TT brakes are working. What are the most likely problems?

[Sunny]

tinkerreknit
What make of brake controller do you have?
My guess would be a short in the trailer brake wiring that is coming and going?

Tom

[tinkerreknit]

Hi Sunny! It's a Draw-Tite Activator. Do you know whither or not a short in that area would keep the controller's LED from lighting?

[xc-mark]

Sounds like a short as stated , if your trailer has the brake wires run threw the inside of the axel thats the first place to remove and replace the wires ! I have found my trailer had the wires run threw the tube from left to right with nothing to support the wires inside so the vibration from the tires chewed threw the insulation in very few miles! Easy fix but just make sure you solder and srink tube your connections so your not doing it twice!

[Jeff_in_The_Dalles]

I'd start from one end and work to the other...

Take the trailer's plug apart and look for frayed wires, loose connections inside, and/or corroded contacts. If it looks a little rough, replace it. They are cheap.

Look over where the trailer's wiring meets the wiring from the axles on the side of the frame. Some people use those little crimp taps when changing magnets, and if yours has those I'd get them off of there. As noted above, also check where the wires go into the axle.

If you haven't pulled the drums for repack and brake inspection in a while, you may as well do that. Sometimes the magnet wire can come unclipped from the arm and get chaffed.

[RIDER]

I have the same controler you have and had the same thing happen , mine was a poor ground on the TV . Disconnect the trailer from the TV then plug the trailer to the plug on the TV ,Do not let the trailer & TV touch It should ground through the plug the brakes shough work if not bad ground on TV or trailer . when hooked up it will ground through ball sometimes ,But grease on ball will cause a break in ground at times . This is what mine was doing on off .not a good feeling .But a cheep fix if this is the trouble if this does not do it then good luck on your search. RIDER

[tinkerreknit]

I want to thank everyone for taking time to help me. I think I will check the ground points on the TT first thing, since almost all my trouble over the years has been with grounding - well except for the time my ex left me for a married man. But that's a different story. It might be a short while before I can report back, but I will keep checking here for new suggestions.

[tinkerreknit]

Hey RIDER, I am wondering what you mean by "TV". I don't want to jump to conclusions.

[Sunny]

He means Tow Vehicle.

Tom

[tinkerreknit]

I wanted to get back to you guys and let you know what the problem was. It was a dirty ground wire connection on the TT. I plugged up without the TT touching the TV and everything worked fine - all the lights and brakes work fine unless I am rolling. Even though the connection to the TT frame didn't appear to be failing, I started there. I Dremmelled a shiny spot and re-attached the lug, then painted over the area. I have since towed quite a bit with no failure of the brakes. Wonderful! Thanks to everyone, again. Notice my signature now....