Factory Brake Controller not working
 

I have a 2008 F-250 Power stroke with tow package. The truck is equiped with the factory electric brake controller. The braking on my goose neck trailer is weak at best. When I use the hand knob for the trailer brakes alone they work fine. We have checked the connection at the master cylinder and it does not appear to be getting the full voltage/amperage. Is there a fix for that?

Check all your connections for corrosion....esp. the one at the rear of the truck. Open up the connector and look inside!

How are you checking output at the master cylinder? You will not get output that is comparable there to manual activation unless you are really hammering the brakes.

For example, you know the trailer brakes are good with full manual activation. You do not get that kind of output with normal truck braking as the trailer braking is proportion to pedal pressure and rate of deacceleration. We get a lot of comments about the factory controller not working, when at times it is due to misunderstanding.

Can you say a little more about how you know it is not working? For example, did it work in the past and not now? Did something change? Are you having a hard time stopping? How big is your trailer and what does it weigh? That information will help trigger more comments. :)

Steve

I have the trailer on jacks and I spun the tire by hand and stepped on the brakes and nothing happened. I then spun the wheel again and used the trailer brake controller only and the tire stopped. Then I put a test light at the plug on the truck and repeated the process. The light was dim when I stepped on the peddle. I then went to the master cylinder, unplugged the rear plug from the bottom and put the test light on it, it was also dim. I did not have a volt meter, so this was the best I could do. It appears though that it is not getting the proper voltage from the source.

Does your brake controller illuminated color turn red instead of green when this happens?

If so, I would bet the connector needs a thorough cleaning and/or checking for proper contact.

If you go to the tech tips at the top of the forum, I did a volt/amperage test a good while back showing how small the controller output to the trailer is by just stepping on the pedal while stopped.

How does your controller do when you are driving and have to hammer the brakes?

Steve

I haven't tried it yet in a driving situation. I have just installed new brakes on the trailer thinking this was the problem and then checked checked the truck. However, from past the brakes never seemed to work that good in driving conditions.
No, the controller never turns colors, it always stays green.

I could be wrong but I was under the impression your truck needs to be moving for the TBC to fully work when applying brakes?

Again, maybe someone will correct me on both comments but I believe in 2006 it was changed so the controller works at any speed. Before it would only work after the 5 mph circuit activated when the door locks auto locked.

Also, if the controller shows green on the console, it is receiving a signal from the brakes, I believe, by way of resistance in the line, eliminating the truck connection at rear bumper.

I agree. 2006 would work stopped.

Yes, it works on manual, but you do not get close to full power using just the pedal, as the amperage is guided by pedal pressure and an accelerometer. You can not test the TBC doing what the OP is doing.

The output amperage on the TBC in my 2010 when set at 10 puts out about 1 amp using pedal pressure alone. I just put my test box on to verify what I posted a good while back. At the same time, it puts out 12 amps using the manual slide. One amp is not going to do anything when it comes to trailer brakes. :)

This comes up so often in this forum because I think the TBC is not well understood. The operation is not as transparent as with older controllers and its action is not always obvious. I never feel mine working when it engages.

Steve

One other feature of the TCB in the Ford is that it mimics the anti-lock feature of the truck!

Well, i took it to the dealer yesterday and they said they found nothing wrong. I then went back and hooked it my trailer and it does not stop. I had the vehicle in gear and stopped, i then held the brake controller over and let my foot off the brake. The truck started rolling forward. I am going to test the trailer this morning with a friends truck (dodge). I will then know for sure which is not working.

Thanks for all the tips and advice, I will keep everyone posted.

How fast were you going when you tried it? Did you get on the highway.....

Are all of your hubs "humming" when the brakes are applied? If not, the magnetic actuators aren't working. I'd go back and check the wiring from the hubs up to the connector again.
It doesn't sound like a short or you'd be blowing fuses.
It sounds like an "open" or a place where there's no current flowing through that point. Amazing the controller doesn't identify that their not working.