Brakes and brake controllers

[EvilScotsman]

I have a conundrum,..an enigma if you will,...the trailer given to me is a dual axle cargo trailer with brakes,..but the issue is how do I tell if it has the brake controller on the trailer or if I need a controller box in my SUV. There is a small black box on the trailer tounge that some people tell me is the controller box so all I need to do is run a wire from my tail lights to the box and the brakes will work. On the other hand I have people telling me that the box is "part of" the controller and I need an actual controller box in my SUV that hooks into the brake light line and then has a wire connected to the box on the tounge,..basically the box inside the SUV is a sensor only and tells the box on the tounge to set the brakes on the trailer. So that is the basis of my issue,.... as Yul Brenner asked in The King and I "How do I know what is really is,..for some things are NEARLY so,..others NEARLY not".

[Lit'l Shinee]

Scotsman,

Could you post a photo of that black box? The brake controller is inside your vehicle and sends power to the trailer brakes through the connector on your vehicle. I am certainly not the end all be all on this subject but just from what you are saying, my first thought is you may be talking about a breakaway switch. It is a small, usually but not always, black box on the tongue and it is not tied into your tow vehicle lights. It is powered off the trailer battery and functions as an emergency stop if your trailer breaks away from the TV. No brakes on my teardrop but this is the setup that I have on my other trailer.

The only other brake items I know of that are on the tongue would be if the trailer has surge brakes. The real pros will probably weigh in soon but seeing the "black box" would really clear it up. You never know what someone may have added.

Welcome and good luck,
LS [/img]

[EvilScotsman]

I will post a better picture soon but in my albumn is a pic of the tounge that you can see the box in.

[len19070]

The "box" on your trailer is supposed to hold a small battery that activates when the "brake-away switch" is pulled, that activates the trailer brakes in case the trailer brakes away from the Tow Vehicle, thus stopping the trailer.

If your trailer has brakes...and you wish them to work, you will need a brake controller on your Tow vehicle.

There is a small black box on the trailer tounge that some people tell me is the controller box so all I need to do is run a wire from my tail lights to the box and the brakes will work. .

This is the wrong info.

Happy Trails

Len

[Trackstriper]

Scotsman,

The small box on top of the frame tube with the cable loop should be your breakaway switch. The rearward box on the inside of the frame should house a small rechargeable battery, about the size of a motorcycle battery. The forward box on the inside appears to be a common junction box for the wiring, you could open it up and see what's inside.

When properly hooked up to the tow vehicle there should be a small wire cable from the breakaway switch that will attach to the vehicle's hitch. If the trailer should accidentally break loose from the tow vehicle, the cable will pull a pin out of the breakaway switch, completing a circuit that sends 12v from the battery directly to the brakes. That should slow the trailer down a bit.

[asianflava]

Yep that's a break-away box. The little cable loop attached to the half round box attaches to the tow vehicle. If the trailer comes off, the loop will pull a pin out of the half round box which will apply the brakes to the trailer via a battery inside the larger box.

I have a brake controller in my truck, I have a Teknosha P3. It is the updated version of the popular Prodigy. The P3 and prodigy have accelerometers inside, they will sense how hard you are braking and apply the brakes to the trailer proportionaly. Mine works like a champ, well worth the money.

[Dale M.]

The "box" on your trailer is supposed to hold a small battery that activates when the "brake-away switch" is pulled, that activates the trailer brakes in case the trailer brakes away from the Tow Vehicle, thus stopping the trailer.

If your trailer has brakes...and you wish them to work, you will need a brake controller on your Tow vehicle.

There is a small black box on the trailer tounge that some people tell me is the controller box so all I need to do is run a wire from my tail lights to the box and the brakes will work. .

This is the wrong info.

Happy Trails

Len

DITTO........ Breakaway switch and battery only on trailer.... Incidentally battery will need regular charging to be effecting, usually done off +12 volt pin on 7 pin connector....

You WILL need a controller in tow vehicle... Get best quality/featured one you can afford.... I will tell you from experience one without any dial or readout (LEDS) on settings is miserable .... I go from towing a empty car carrier (very little brakes needed) to having 5000lb vehicle on trailer for a total with of near 6,500lbs (heavy breaking) and its always a battle for first few stops to get braking percentage right with uncalibrated slider on controller....

Here is Basics.....

http://www.championtrailers.com/Electri ... wiring.pdf

More can be found with GOOGLE search "electric trailer brakes wiring"

Also found this pretty cool site that mentions some about trailer wiring and brakes....

http://www.etrailer.com/faq-wiring.aspx

Dale