Unless you have a new truck with built-in brake controller, the aftermarket controller you install will only plug into the existing wires, there is no interaction between the vehucle systems and the controller. Most controllers are pendulum types that act based on the swing of an iternal pendulum to activate the brakes, the further the pendulum swings, the harder the brakes apply.
My limited understanding is that there are several schemes out there and, as you might expect the more you pay the better they are.
Cheap controllers like the Hoppy I have use what they call time delay. The only imput is from the brake pedal switch. It "knows" from the electical signal to the brake lights that the brake pedal is depressed. The problem is you get the same amount of trailer braking irregardless of if you're going 2 mph or 70 mph which makes slow speed driving impossible without manuall adjusting the "boost"
Next up are units like the Prodigy. This senses not only that the brake pedal is depressed but how fast the vehicle is slowing. I think it uses a solid state inertia senser. Older controllers used a mercury switch and angle of the controller critical. The problem is if you're maintaining a constant speed, like going down a mtn pass for example, the inertia sensor reads zero so even though you may be applying a lot of braking to maintain your speed you don't get the level of boost you need. There's other "games" they play like keeping track of how long the brake is depressed and most people report very satisfactory results.
In the "olden days", circa 1972 the controllers worked without the benifit of computer chips. The way I remember them working was a mechanical linkage to the brake pedal that was attached to a mechanical resistor (rheostat). The farther you pushed the brake pedal to the floor the less resistance was applied resulting in more current/boost going to the trailer brakes. In my opinion this was superior to any of the modern wonders. Dirt simple, not computer chip to fry, inexpensive and true proportional braking. There was also a knob on the front of the controller than moved (left to right) when the brake was applied and this same lever could be used manuall to apply a proportionate amount of brake to the trailer. A much better driver interface than the electronic ones of today. I think the Jordan uses this principle with the addition of modern electronics. The Jordan isn't as common as the Prodigy but it's owners are equally if not more enthusiastic about it.
Some of the new trucks have a factory contoller that actually senses hydrolic pressure in the master cylider and applies a proportional amount of break to the trailer. This should be the ultimate in trailer brakes. There is one aftermarket company that uses this system as well.
Hopefully someone will correct any mis-information I've spewed out here,
-Bernie
Excellent recap of brake controllers. The only thing I could add would be the old-timey controllers (Kelsey-Hayes) used a hydraulic linkage from the brake line rather than a mechanical linkage. They worked great, but got left behind when ABS braking became popular.
I certainly agree they were better than anything today, except maybe the Ford TowCommand system, which is the same type of linkage.
The three main high end controllers are the Prodigy, which works off inertia, the Jordan which works off brake pedal position, and the one that works off the hydraulic pressure like the old ones except that it has smarts not to interfere with the new ABS.
Each has its proponents and debates about which is best can be fun (!) to watch. The argument mentioned above about constant downhill speed is one of those that can fun to tear to shreds with both logic and experience, for instance.
The reality is that all these high end brake controllers provide excellent braking. Do watch out for incompatibilities with the new disk brake systems, though.
bhayden is correct ,the prodigy does what he said on a downhill steady
runs ,push on the brake and the controller doesnt see the effort so it does not ramp up the voltage to the trailer ,my only real yet biggest complaint .
My 68 IH travelall has that kelsey hays unit and resistor setup ,its on the
old parts shelf in place is the prodigy ,i agree it would be better if I left it in place i think at this point.My RV guy thinks Im crazy about the downhill
operation of it ,Im not ,anyone have a solution ?
The Prodigy, like most other 'smart' controllers will apply braking when it sees the brake lights go on. On the Prodigy this is used as a part of the 'boost' setting.
After you have pressed the brake enough to get lights, any change in speed will cause a corresponding current to the trailer brakes.
If pressing on the brakes and going downhill does not cause any change in speed, trailer or not, then I think you need to get some brake work done.
The Jordan advocates use this to 'prove' the superiority of their controllers as that one follows the brake pedal directly. The fact is though, that there really isn't that much of a practical difference.
Try it. You'll see.
The hydraulic based controllers on pre ABS vehicles were simple and worked very well. No electronics. Just a hydraulicly controlled rheostat The resistor to adjust the current was usually under the hood. With newer controllers such as the prodigy, this adjustment is on the device and is an input to the control circuit rather than a series limiter.
The trucks with the built in controller are the ones with the edge, I think. These are usually tied in with the vehicle control electronics and can detect slipping, engine braking, and other conditions and make an appropriate response.
I remember back in 1952 (I was 14) dad had electric, I think it was electric, brake controller on the family Nash to brake the 26' Pan Amercan we towed from Detroit to LA. via RTE 66 then up to SF on Highway 1. I remember he manually operated the brakes with a lever that looked liked an oversize turn signal lever on the steering column. I was not that interested in it but I don't recall any dramatic stops though. I guess the old days of trailering were simple.
Neil.
I remember back in 1952 (I was 14) dad had electric, I think it was electric, brake controller on the family Nash to brake the 26' Pan Amercan we towed from Detroit to LA. via RTE 66 then up to SF on Highway 1. I remember he manually operated the brakes with a lever that looked liked an oversize turn signal lever on the steering column. I was not that interested in it but I don't recall any dramatic stops though. I guess the old days of trailering were simple.
Neil.
That sounds like the setup Ricky had in the Long Long Trailer movie. Trailer Brakes!!!! Trailer Brakes!!!!
That sounds like the setup Ricky had in the Long Long Trailer movie. Trailer Brakes!!!! Trailer Brakes!!!!
I do believe they were the same kind of brakes. When that Ricky and Lucy movie came out my parents took my brother and I to see it. We did have our kind of L L Trailer adventure so they got a kick from that movie. I just bought the movie to try and remember why they thought that trip was so funny. I remember a lot of frustrating days....well I could go on but in summary..WE MADE IT!
Neil.
Great question because lots of people think they are fed by the onboard computers and they are not, at least none that I am aware of. We sold thousands of Jordan's over the years and it was and is arguablly one of the best ever made but no interaction with the CPU or hydraulics. The old hydraulic systems were awesome too and the brakesmart is the only company willing to test those waters again. Not sure what up with them or if they are still available. They had issues but a good product from all I heard. We simply decided not to get involved with the modification of the master cylinder, however safe you want to believe and I think it probably was. On the other hand, if you want something that will stop you, the Prodigy is a good choice, it does work, just not as good.
Does this sound like the Rom-co dude...Wait, there's more! Hang in there until the first of the year and the new Jordan Ultima "Plus" might be out and it solves ALL problems! We will announce it as soon as we have firm information. We are Jordan Research's largest distributor, as far as we know. Get a Prodigy to get you by though. Not knocking Prodigy folks, you just have to compare for yourself and there are pages and pages of comparisons if you search the web.
the brakes are great ,12" discs up front and 12" drum in the rear.i can tow
the tradewind and stop it without trailer brakes if needed. I believe you have the answer with the boost selection.I have not tried it on the boost .It works very good on normal range ,no boost ,adjusting the gain knob .The boost setting if does as you have said will solve the problem.As long as the
controller isn't looking for the pendulem swing on decents on long grades ,
I think im in good shape.Its really this one long decent ,the Questa grade
going to San Antonio lake (ralley place in october)that this happens on.
It is steep and you gain downhill speed fast ,so you would be using the brakes alot to control the speed .I can leave the manual 5 speed in third
if I need to .
Thanks for the link 2air. The controller Hensley is selling (ubc) sounds like one of those that uses a pressure sensor on the brake pedal. Since that is a bit different from Jourdan's pedal position sensing, I guess that is a fourth type. But boy is the hype bad. They are using 70's era or current bottom end controllers for their referent. The hype is also contradictory about sensing trailer brake type.
Randy should take a look at my previous post. BrakeSmart is still a popular controller for those who like the hydraulic sensing basis. As usual, there is significant brand loyalty by those owners, too!
All of these modern, call them second generation controllers, have intelligence built in. What I call first generation automatic brake controllers are those that you found in the 60's and later that were simple hydraulic controlled rheostats. Third generation would be those integrated with modern vehicle control systems.
I have yet to see any evidence that the manner of sensing is a significant factor. Whether it is interia (e.g. Prodigy), pedal position (e.g. Jordan), pedal pressure (e.g. ubc), or hydraulic brake pressure (e.g. brakesmart), the good ones all use at least one other input - brake lights - and then apply smarts to figure out what to do. They also usually have some settable inputs such as the initial boost and overall sensitivity.
The hydraulic sensing illustrates this difference. It used to be (gen I) that the hydraulic pressure did the work. In gen II it is only sensed and then analyzed to determine proper brake current controlled electronically. The action - trailer braking - is isolated from the sensing.
The issue of trailer brake type seems to be one some folks are encountering when they modify electric drum brakes to a hydraulic disk brake system on their trailers. The ubc brags about pulse width modulation for braking current. This is good for the drum brakes but not for the disk brakes. Earlier Prodigy controllers had problems like this with disk brakes but it appears a ROM upgrade has fixed that. I don't know about the others. (this is analogous to the modified sine wave debate with inverters)
The lag between requesting brakes and having brakes is an issue even without a trailer. These gen II systems use the brake light to anticipate need in order to reduce this lag.
The effect of temperature (mentioned in the ubc hype) is also significant for magnet brakes but not so much for hydraulic (disk) brakes. In this, I'd think the Prodigy would have an advantage because it could compare braking action to braking current and make appropriate adjustments. Others have to compare secondary brake need to current for comparisons.
Then there is the holding stop issue like at a light. A good controller will usually reduce current for electric brakes if it detects this condition to reduce magnet heating.
There are a lot of other issues and special cases to be considered. I expect to see gen II controllers get smarter about these but I doubt they will ever get to the gen III integrated type capabilities. The fact is that a lot of learning is being encoded in vehicle system software and that is one of those near invisible things that adds up to make a big difference in safety and comfort and reliability for all of us.
Quick Links
Linear Mode
