trailer brakes lock up less than 5mph?

[The motor guy]

I have a prodigy p3 brake controller and occasionally it will max out on the setting. Usually it's at low speeds less than 20mph. So I have it set at 6 and it will go all the way to 5 or 6 with just normal pressure on the brake pedal. Why does it do this? It doesn't do it all the time, maybe a few times a week, but I think it's locking up the braking tires when it does it at 5mph.

 

[The motor guy]

Also you're supposed to do a stop from 25mph using the boost lever to see if the tires lock up and they don't, so I don't even have it set at the max setting for the load.

 

[copcarguy]

On my prodigy you can set it for small, medium, or large trailers.

It'll show you a picture of a truck towing a larger and larger trailer.

Depending on this setting, is how much initial braking force is being sent when you hit the brake pedal.

If you experience lockup randomly, maybe check for proper grounds?

 

[copcarguy]

Or also is it set up for straight electric or electric over hydraulic?

 

[64bawagon]

Mine will do that also, always after driving for a while and in stop and go traffic.

 

[The motor guy]

The truck i tow it with weighs 7000 and the trailer weighs 4000. I find if I turn the boost off completely I have to set the brake power closer to 10 or 11 to get the same breaking power and it only goes to 14 so having it all the way up for such a light weight trailer doesn't seem right. I'm pretty sure it's the boost that causes it to lock up and randomly go to full stopping power in stop and go traffic.

 

[The motor guy]

It only does it if it happens to apply the brakes fully, which is why I'm wondering if it's just a glitch in the brake controller or what, cause you tap the brakes and the truck stops immediately.

 

[mk378]

The unit must be mounted properly for the inertial feature to work. When the "boost" is off it operates on inertia. They don't recommend using higher than B1 boost if the trailer is lighter than the truck.

 

[CKN]

Have you had the trailer brakes adjusted? I find every so often they need to be adjusted by hand from the access slot on the back of the drum.


If it's set to max setting then I would say the brakes on the trailer are out of adjustment.