ccc150

On my 150, the display shows braking action with the foot pedal and squeezing the controller. However, I do not hear the buzzing at the trailer wheel with the foot brake only with the controller. Would that indicate the pressure transducer?

PerryB

I don't think so. The system ramps down below a certain speed. I want to say 10 mph but I'm not sure. What happens with the controller on "10" and a stiff brake application -foot pedal - at 25 -35 mph?
Controller failures are pretty rare unless the systems been mis-wired or back-fed. Transducer failures almost never happen, but the possibility exists. I've worked on a LOT of electric brake systems over the years, both factory and aftermarket controllers, and the overwhelming majority of the problems lie with the trailer or the connector/plug.

ccc150

PerryB, My TBC was factory installed and for 17K miles always was set at 6.5 and worked as advertised. Now I can have it at 10 and no brake with the foot pedal. I do not think that it would be the trailer wiring since it works all the time squeezing the controller. When you say it ramps down at or below 10MPH does that mean I should get no foot braking unless above 10MPH? I am only testing this when not pulling the RV at our camp site.

ccc150

I realized we had no TBC on the way to Florida even set at 10. WE have a ProPride hitch which works great but is a pain in the a** to hook up and would rather not if testing at idle is OK.

I think my question should be "Does the TBC activate the trailer brake while not moving or does the whole rig have to be going +10 MPH"?

PerryB

I'd have to go back and do some more homework on the Ford system, but I'm pretty sure it tapers down below about 10 mph, but you still should be getting something. I agree if the manual activation gives you good trailer brakes, something is wrong with the controller, not the trailer. If 6.5 was the original number that you were using, 10 should give you locked tires.

PerryB

Also, does it ever throw any messages? "Trailer disconnected" means an open circuit-- the truck isn't seeing enough load to indicate a healthy array of magnets, and "Trailer fault" indicates a short.

** edit -- sorry, I got my wires crossed on sending a private message, it was to someone else. Senior moment .....

ccc150

I agree about getting at least some current to the brakes when not moving. It always worked great at 6.5 but nothing at 10. From Wikipedia, read that Ford's TBC comprise of 3 parts. There is the controller itself, the TowCommand master cylinder with a pressure transducer, and the PCM (power train control module)

https://en.wikipedia.org/wiki/Ford_TowCommand

ccc150

The display has not shown any unusual messages about this. WE will find out today. My time in Florida is running out. We have to leave for tomorrow for home in Ohio so I have an appointment today at Kelly Ford In Melbourne to diagnose the problem. I will post the results.

Krippendroph

Mines the exact same thing. All displays indicate everything is fine. Safe Travels to you on your return!

Krippendroph

Hey, how’d ya make out at the dealership?