Trailer Brake Controller
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Trailer Brake Controller
I have a 2012 Ford F 450 which has a TBC unit in the truck,when connected to my 25ft caravan which weighs 8000lb i have problems stopping the rig. It comes up on the screen and says its connected have checked brake lights and all works.The brakes feel like they are working at 50% any help would be greatly appreciated
Cheers
Baker
Cheers
Baker
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From: Frederick, MD
Check the gain, but there are some other things to check as well.
Simple test is to use the manual slider and have someone listen at each brake drum for a buzz.
the Buzz indicates there is at least power to the magnets.
You can also pull forward at about 25 mph and use the slider to see how the trailer brakes engage.
You may need to adjust the brakes. You can adjust just like the brakes on a car or truck with drum brakes.
Jack each wheel up and adjust accordingly.
Simple test is to use the manual slider and have someone listen at each brake drum for a buzz.
the Buzz indicates there is at least power to the magnets.
You can also pull forward at about 25 mph and use the slider to see how the trailer brakes engage.
You may need to adjust the brakes. You can adjust just like the brakes on a car or truck with drum brakes.
Jack each wheel up and adjust accordingly.
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From: Frederick, MD
Yeah, next step is jack up a wheel and have someone apply the slider and see if it even slows the tire down as you slide it.
Most likely a brake inspection or adjustment is needed if you have the power at each wheel.
Most likely a brake inspection or adjustment is needed if you have the power at each wheel.
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Senior User
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From: Hillsboro, Oregon
Possible not enough voltage is going to the brakes. May not apply to you since you already did some checking but last summer while coming back home from a trip it felt like I had to brake harder to slow down. When I got home to check it out I found the brake wires got pinched between upper leaf spring and frame of trailer which just about cut the wire in half.
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Went and did some more investigating,and checked out the towing menu in the truck,it is set up on electrical but when you scroll down it says electric/hydraulic which one should it be on.
Cheers
Baker
Cheers
Baker
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From: Frederick, MD
Electric. If you have disc brakes on the trailer then it might be the other.
You should have 3 amps at the wheels btw. 3X4=12 amps coming out the rear of the truck.
did you listen for the buzz at each wheel or did you have someone else do it?
You should have 3 amps at the wheels btw. 3X4=12 amps coming out the rear of the truck.
did you listen for the buzz at each wheel or did you have someone else do it?
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From: Frederick, MD
Then if there were no sounds at the drums...you try to listen.
Time to check for power at the plug on the truck. I would advise taking it apart and checking the connections for dirt, rust and loose connections.
Time to check for power at the plug on the truck. I would advise taking it apart and checking the connections for dirt, rust and loose connections.
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TBC
Hi Scott sorry for not getting back sooner as i have had a few issues to deal with.
Just some feedback i have checked power at the plug which reads 12volt,i have moved the slide and it says the same,but when i put my foot on the brake it reads 2volt,any thoughts would be greatly appreciated.
Cheers
Baker51
Just some feedback i have checked power at the plug which reads 12volt,i have moved the slide and it says the same,but when i put my foot on the brake it reads 2volt,any thoughts would be greatly appreciated.
Cheers
Baker51
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Not all brake magnets will buzz, mine don’t all the time. The TBC is solid state (transistors,,etc) which might be hard to diagnose with just checking voltage, Not to sound too technical but Power (amps x volts) is measured in watts. I bring this up because the TBC can put out 12 volts but restrict current flow. Like Senix stated, each brake magnets draws 3 amps to produce its maximum braking.
That said, I have a brake controller tester that simulates up to four brakes. With a Ford TBC the controller takes inputs from the truck to determine how much Power to send to the trailer brakes, this is why the brakes don’t lock up, the slide bypasses all inputs from the truck.
For example the TBC doesn’t activate the trailer brakes if the vehicle is not moving over a certain MPH. I’m guessing this is why when you stepped on the brake pedal you measured 2 volts.
You haven’t given enough information from your testing for us to tell you. You said that you did the first 4 things but didn’t give the out come.
The first thing if your trailer brakes are adjusted is to try to move the slide right over and this should bypass the TBC electronics, if the trailer wheels lock up then most likely the trailer brakes are ok. In <st1
North America a travel trailers have a break away cord, this applies full power to the brakes from the battery in the trailer in the event of the hitch disconnecting on the road. If you have this it should also lock up the brakes. Then maybe try your trailer with another vehicle if you can. Then it would be time to test the TBC.</st1
FYI:
The TBC takes the speed, brake pressure among other things from the truck into account to put out a certain output, so testing it in the driveway without moving and understanding how its works would be hard to get something conclusive. Also the brake lights are a separate circuit so they work even if the TBC is not.
That said, I have a brake controller tester that simulates up to four brakes. With a Ford TBC the controller takes inputs from the truck to determine how much Power to send to the trailer brakes, this is why the brakes don’t lock up, the slide bypasses all inputs from the truck.
For example the TBC doesn’t activate the trailer brakes if the vehicle is not moving over a certain MPH. I’m guessing this is why when you stepped on the brake pedal you measured 2 volts.
You haven’t given enough information from your testing for us to tell you. You said that you did the first 4 things but didn’t give the out come.
The first thing if your trailer brakes are adjusted is to try to move the slide right over and this should bypass the TBC electronics, if the trailer wheels lock up then most likely the trailer brakes are ok. In <st1
North America a travel trailers have a break away cord, this applies full power to the brakes from the battery in the trailer in the event of the hitch disconnecting on the road. If you have this it should also lock up the brakes. Then maybe try your trailer with another vehicle if you can. Then it would be time to test the TBC.</st1 FYI:
The TBC takes the speed, brake pressure among other things from the truck into account to put out a certain output, so testing it in the driveway without moving and understanding how its works would be hard to get something conclusive. Also the brake lights are a separate circuit so they work even if the TBC is not.