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Having trouble with my trailer brake for 5th wheel being pulled by F350. Seems that when I manually apply the lever on my brake control the brakes on the trailer seem to work properly but when I step on the brake they don't and there is no green light that turns to red as I do it. Don't know where to look The wiring seems intact at the plug on the truck connection wise. Brake control lights work properly when done manually. Thanks for any help. This just happened all of a sudden with nothing else being done to the truck or the wiring

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Sounds like the wire coming from brake to controller. Is there by chance an inline fuse on that wire ? or probably a wire connector when the controller was installed.

Jim Spence

2000 Dodge 3500 1 ton QC 4x4 dually 5.9 diesel LB

BD exhaust brake, 6 spd manual trans

34CKTS Cedar Creek 5er, Trail-Air hitch

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We have a 2011 Ram 3500 with the factory installed brake controller. It does not send a signal to the brakes unless the rig is moving. If I press the brake pedal at a stop, no signal is sent. I was surprised when I found this out. A Ram dealer said that is the way ours is supposed to work. I don't know the make of this controller but perhaps you have the same brand. ????

The richest are not those who have the most, but those who need the least.

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On the brake controllers I've installed (several) there are basically four wires. 1) Hot 12 VDC,,,,,,,,,,2) Ground,,,,,,,,,,3) Blue which is the control back to activate the trailer brakes,,,,,,,,,,,4) Brake light circuit which is hot ONLY WHEN the brake pedal is depressed, its the 12 volt signal that illuminates the trucks brake lights and may be via a micro switch on the pedal itself which is energized if the pedal is depressed. Some of those brake light switches are adjustable, but if the trucks brake lights are working that's (switch) NOT the problem (could be a wire/connection problem from it to the controller).


If to the controller there is 12 VDC power (1) and Ground (2) and the Blue (3) Output to the controller, if you manually push/slide the lever on the controller I would suspect that will indeed send power to the brakes and they will work EVEN THOUGH THE BRAKE PEDAL ISNT DEPRESSED AND THE BRAKE LIGHTS ARENT ON


My best pure guess not being there and not having your controller diagram IS THE CONTROLER ISNT RECEIVING THE 12 VDC BRAKE LIGHT SIGNAL WHEN THE PEDAL IS DEPRESSED as its supposed to do.


If you take a 12 VDC test lamp and ground one end and touch the probe to the controllers wire (1 of the 4 ) that's the brake light input signal, if you depress the pedal with Ignition on maybe??? and/or maybe has to be running?? IT SHOULD LIGHT UP. If not I suspect a bad wire or faulty connector or the pedals brake light activation switch is bad. HOWEVER if the trucks brake lights are working that rules out a defective brake light switch so I suspect a bad wire or connector or plug etc.


If pressing the brake pedal doesnt activate the controller (Blue output to trailer brakes) yet the brake lights work and manual activation powers the brakes, I suspect the stop/brake light signal isnt getting to the controller when the pedal is depressed.


NO WARRANTY not being there and no info about your truck or controller, just my best pure guess




John T

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Could this note from the installation instructions be related to the problem?


WARNING This brake control is activated
by inertia and requires the level to be set
properly, or the braking response will be too
harsh or ineffective.
To properly level the sensor, the trailer and
tow vehicle must be parked on a level surface
and trailer must be connected to tow vehicle.

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure



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Connect trailer to tow vehicle, Bi-Colored
Light should glow GREEN.
Set power knob to maximum by fully
rotating clockwise.
Depress tow vehicle’s brake pedal and hold.
Rotate the Level Knob counter-clockwise
(towards the back of the control) until the
Bi-Colored Light starts to change colors
from GREEN to RED.
Carefully rotate the Level Knob clockwise
(towards the front of the control) until a
shade of ORANGE is visible.
Bi-Colored Light should show:
• DIM ORANGE for a typical setting.
• BRIGHT ORANGE for an aggressive setting.
• DIM RED for a more aggressive setting.

Release brake pedal


Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure



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