Trailer Brake Controllers Explained

[MountaineerGreen]

I found a great article on www.etrailer.com here.

Trailer Brake Controllers

An electric trailer brake controller is a device that supplies power from a vehicle to a trailer's electric brakes. There are two types of electric brake controllers - Time Delay Activated ("solid state") and Proportional ("pendulum style"). Although the controllers' methods are different, both types of controllers are very similar. Both allow the user to adjust output or braking power. Both have a pressure sensitive manual override trigger that can be used to apply the trailer brakes independent of the vehicle brakes. Both have the same wiring configuration.

Time Delay Activated

Solid state controllers are "enabled" by the brake pedal switch and apply a gradual voltage to the trailer's brakes using a Time Delay Circuit.
Advantages : Time Delayed controllers are inexpensive, have a low profile, and can be mounted on any angle (very user friendly).
Disadvantages: When towing (in most applications) with Hazard flashers on, the Digital Display will flash with the Hazard Flashers. If the Brake Control is set aggressively, pulsing may be felt in the trailer brakes. However the Pulse Preventer will isolate the Brake Control from the flashers and eliminate the flash/pulse situation.

Proportional

Pendulum Style Controllers are "enabled" by the brake pedal switch and "activated" by a Pendulum Circuit that senses the vehicle's stopping motion and applies a proportional voltage to the trailer's brakes. When properly adjusted the trailer will decelerate at the same speed as the tow vehicle. This increases braking efficiency and reduces brake wear.
Advantages: Pendulum style controllers operate well under adverse braking conditions and have a smooth braking action.
Disadvantages: Most inertia-activated controllers are bulky, more expensive, and must be mounted and calibrated level. The Tekonsha PRODIGY™ and Valley Odyssey™ proportional brake controllers are the exceptions to these disadvantages.

Wiring Configuration

Hitch Supplied Brake Controllers require 4 wire Connections:

1. Trailer Feed (usually blue) - This is the wire that supplies brake power for the controller to the 6-way or 7-way trailer connector at the back of the vehicle. Some vehicles with factory tow packages already have this wire run from under the dash to the rear of the vehicle. Otherwise, the wire is run along the underside of the vehicle and through the firewall to the desired Brake Control mounting location. To get through the firewall, sometimes a hole must be drilled. However, grommets or pre-existing holes are often available.

2. Ground (usually white) - This wire is connected from the brake controller to any reliable ground source.

3. Brake Switch (usually red) - This can be found near the top of the brake pedal. There are wires extending from the switch and using a test light, the wire that has power when the brake pedal is pressed down can be found. This wire is tapped into using a scotch lock.

4. Battery Power (usually black) - This is the connection that supplies power to the brake controller. Some vehicles with factory tow packages already have this wire run from under the dash to the battery with some kind of circuit protection. Otherwise, a wire must be run through the firewall and connected directly to the battery with an in line circuit breaker.



Generic Wiring Diagram





To provide assistance in the hardwiring of brake controllers, brake controller install kits are available. They provide the needed wire that runs the length of the vehicle to the trailer connector, as well as the trailer connector, fuses, and wire connectors. A kit is available for both 6-way and 7-way trailer connectors.

Recently vehicle manufacturers have started installing OEM harnesses under the dash. Adapters are made that will connect to the brake controller and plug into the harness. If the tow vehicle is equipped with a tow package and has a factory installed 7-Way trailer connector then a brake control adapter may be all that is needed.

['97 V8]

Awesome Evan!

[MountaineerGreen]

I use a time delay brake controller in my truck. It is a basic controller, no frills.

I mounted it to the dash, near the console. It doesn't interfere when I am driving and works OK. People swear by other more expensive, Proportional controllers, but I personally couldn't justify the cost for no more often than I tow.

Picture of my install-



I did a custom install for my 7 pin RV style plug, I didn't want it hanging down below my hitch or bumper since I use my truck for offroading. I cut a hole in my bumper and mounted it to the side.

[John_Rock]

Originally Posted by MountaineerGreen

I did a custom install for my 7 pin RV style plug, I didn't want it hanging down below my hitch or bumper since I use my truck for offroading. I cut a hole in my bumper and mounted it to the side.

Stealing my idea huh? Where's my credit?

I did mine back in January 2004. For the same reasons as you. I felt, if I ever offroaded this truck I didn't want it hanging down. Looks much neater in the bumper. Sure was fun drilling the hole.

[John_Rock]

I have my brake controller in the same place too.

[MountaineerGreen]

what did you cut your hole with?

I marked out my line, then cut with a die grinder and cut off wheel. Then used a smaller stone and file to make the plug fit.

Weird how yours looks just like mine- it just worked out just right that way for me.

[John_Rock]

Originally Posted by MountaineerGreen

what did you cut your hole with?

I bought one of those drill bits to make holes in doors for door knobs. I think it was the 2" one.

[Gator Jeff]

Bringing this back from the dead. Sweet set up. I just rewired my 6-pin plug, but never liked how it hung down. I think I have a project in the future!

[MountaineerGreen]

I really like mine still to this day- no clearance issues, if it had been hanging down, I'd pulled it off many times by now.

One tip- depending on how you cut your hole- remove any plastic nearby. When I cut my hole, I used a die grinder and cut off wheel. The hot metal I cut embedded in the plastic and subsequently rusted.

[Gator Jeff]

Originally Posted by MountaineerGreen

I really like mine still to this day- no clearance issues, if it had been hanging down, I'd pulled it off many times by now.

One tip- depending on how you cut your hole- remove any plastic nearby. When I cut my hole, I used a die grinder and cut off wheel. The hot metal I cut embedded in the plastic and subsequently rusted.

Thanks for the tip. I realized I don't have access to an outdoor plug though. I don't think my 14V Cordless drill could hack it. Hmmmm , I think the maintenance area has an outlet outside. With what I'm paying for rent, I think they owe me a kW or two.

[ronniew]

I just bought my explorer in october and it had some wires hanging, come to find out it was the connector for the trtailer connections. who ever ran it did it wrong. they ran a power line from the battery along the outside frame rail then had wires hanging every. I cut it all out. where can I get the pieces to run it correctly. I like to have it look good, not half fast and looking bad.
any help would be appreciated.

[EmilioD]

What type of signal does the controller send out to the trailer brakes?
Is it just 0-12V depending on the force the controller determines is needed?

I have heard 3-5 amps per brake (so two per axle) is that a reasonable number?

The reason I ask these things is that as a project I am designing a circuit to do basic braking. I have found literally hundreds of diagrams which show all the wiring possible until the controller, which everyone shows as just 4 pins. I would like to know what the controller is doing. I understand the diffrent types and how they work, what I want to understand is the output side of the controller.

any info would be greatly appreciated.

[thebrakeman]

1. The better proportional controllers are not "pendulum" activated, but use actual accelerometers (no moving parts). These are the Prodigy, P2, and P3 units by Tekonsha.

2. Disadvantages of the time-delay units go far beyond flashers and pulsing. In stop/go traffic, people usually back off on the gain so it's not "pulsing". But if you back off on the gain, then some kid runs out in front of you, it could take several seconds for full braking to kick in. Too late if you hit the kid. So you have to choose between comfort and performance. Not a choice I want to make.

3. Most people that say the extra cost isn't worth it, have never used a good controller.

When you have so many thousands of dollars tied up in an SUV and a camper (or expensive equipment in a utility trailer), I can't understand why people will not spend another $50 to get the best braking possible. You could save a life, and/or avoid an accident.

If you are shopping for a brake controller, skip the cheap time-delay controller, and spend the $100 on a Prodigy.

[pintopaul]

i have an 08 sport trac with factory 4 and 7 round but no place for the brake controller to plug in, i have even taken it back to the dealer cause they say it has to have it . but still nothing they had to call ford to find out where it is.it has all the wiring on the 7 round up to the fuse panel under the hood and a 30 amp fuse but no wire under the dash.... anyone have an explorer with one from the factory? i need help finding it... i hate to cut into the factory wiring if its already there. thanks paul

[MountaineerGreen]

Paul, if your ST has the factory towing package, it has to be there. It is likely just a plug somewhere tucked under the dash or attached to the firewall, brake controller manufactures make harnesses designed to plug right in. My pickup came with a pigtail to wire to one, though I have never installed it. I'd suggest getting a harness or pigtail, get a good flashlight and get down and look under the dash. It has to be there.

[pintopaul]

i was hoping someone had a newer explorer and put trailer brake controller on theres to give me some idea of where it was located. i have crawled under the dash on the drivers side and passangers side but not able to find it, i went to my dealer and the service guy said it should be right here but he was wrong...........

[MountaineerGreen]

It may be just a socket on the fire wall- I suggest you get the pigtail and you can find where it plugs in. The best way is with the plug in hand.

EDIT: Drivers side, near the center stack of the dash.

[thebrakeman]

You need to look for a rectangular female socket, NOT just wires. Factory tow package on Fords (unlike GM) gives you something to plug into.

On my '06, the socket is approximately 4 inches to the right of the parking brake pedal. But it's not back on the firewall. The socket is mounted forward, near the park brake release lever. Slide the seat back, and lay down on your back with a flashlight. The socket is rectangular. The socket has space for 6 wires, but only 4 are used. The open end of the socket faces toward the front of the vehicle...that is, you will plug in the harness from the front to the rear.

PS - If you do have the factory tow package (and it sounds like you do), you should have a Ford brake control harness provided either in the glove box, or wherever your jack is stored. This will have the male rectangular plug at one end, and bare wires at the other end.

If you get the Tekonsha Prodigy brake controller (I HIGHLY recommend it!), you can also get a Ford specific wire harness that has the appropriate plugs at each end. No splicing or butt-connecting required.

[pjw73nh]

I have a 2008 Limited. After a lot of looking for the trailer brake controller connector, I had someone with a smaller head get in there and find it for me. I posted a few pix here.

https://picasaweb.google.com/1039561...eat=directlink

I couldn't figure out how to do attachments in the forum. Hopefully they'll help a few folks out. I'll keep the link live for a while. Perhaps someone can post them here on the forum for others to use.

Hope it helps.

Best.

P.....

[thebrakeman]

Looks like the orientation of the socket can be different year-to-year, but that's the same location as mine, and I think the same gray color.