Where can I find troubleshooting info peculiar to this system? Will take to dealer asap but I would like to check basics until I can get it scheduled. The on-dash manual control works great (applies trailer brakes) indicating wiring and connectors are OK. But when the brake pedal is applied the trailer brake lights work but no voltage to brakes. All the fuses I have found marked trailer brake check OK.
Any tips or info will be appreciated. Thanks.

 

Did you go through the process of setting the gain? The steps are in the owner's guide.

 

Yes. I also measured voltage at connector. With the gain set at "10" for test purposes I measure 12 volts at the connector when using the manual control. When I have someone press the brake I measure 1 volt. It seems like a bad controller but I don't have a schematic or tech data other than the owner's manual.

 

I just found the following at etrailer.com. If I have a proportional (pendulum controller) then I guess I have jumped the gun in my ignorance.

" Proportional Pendulum Style Controllers are "enabled" by the brake pedal switch and "activated" by a Pendulum Circuit that senses the vehicle's stopping motion and applies a proportional voltage to the trailer's brakes. When properly adjusted the trailer will decelerate at the same speed as the tow vehicle. This increases braking efficiency and reduces brake wear."

Thank you for your input which helped get my brain in gear.

 

Back at square one. Controller has proportional output based on vehicle brake pressure. I get only 1 volt with heavy pedal pressure. My guess is bad controller or bad pressure sensor on master cylinder unless someone can give a more educated response. Thanks

 

Actually, there's always been a hoopla about the integrated controller not working unless the vehicle is travelling 15 mph or more, and of course this upsets 5th wheelers who want to test the integrity of their hook up.

Supposedly this was fixed in about March? '05, but who knows, maybe you got an old one nonetheless.

Maybe you could run a couple of test wires from the trailer brakes back to a VOM in the truck, then take a reading while braking at about 25 mph.


Another thing occurs to me as well. Does your controller turn green when the truck powers up? If it is still red the electronics are finding your trailer at all, and won't apply any braking voltage.

 

That should read:

Another thing occurs to me as well. Does your controller turn green when the truck powers up? If it is still red the electronics AREN'T finding your trailer at all, and won't apply any braking voltage.

 

I have the old controller on my pre March 2005 build date F - 350. As such, the brakes do not work unless you are moving 15 mph + -. To check if that is the controller you have, drive on road and manually apply trailer brakes. At stopped position 1 volt or less goes to brakes. Not a failure, as per Ford. They have a bulletin out that explains in greater detail. I think it sucks, but doesn't suck enough to replace. Allegedly not a problem at a DOT stop, which I truly question.

 

It seems being in motion is the solution. After setting gain as per manual, using the foot brake at 20 mph, with the windows down, I can hear the trailer brakes engage. The build date on truck is 10/2005. Thanks for all input.

 

Glad you got it figured out Ron.