brake controller

[menoble]

Went to the RV store with every intention of replacing my old Voyager brake controller with a new P3 before last weekend's trip. Although my initial brake problems were with the cord connector, the Voyager has always been a pain to get adjusted just right. In a moment of stupidity, I let the clerk talk me into "the one we install in 95% of the new rigs". It looked OK, had the digital readout and the manual override, was self leveling and short-circut protected, and 1/2 the price of the P3! Installed the new unit and took a test drive, it worked fine up to about 60% of output and then it flashed the short circut code. Checked continuity to ground, connections, lifted each wheel and checked all the brakes, all good. Still flashed SC when I pushed too hard, but I thought I'd give it a few hundred miles to settle in. You can tell where this is going. Tootling down the road we go in heavy traffic, we're all happy and then suddenly the brake lights come on ahead of us, no problem, the trailer brakes alone at full power are enough to slow the whole rig. 10-15-25-35-55-SC!-SC!-SC!-SC! Grab the manual lever, same thing SC!-SC! Sort of defeats the whole purpose of a trailer brake if the controller won't energize them. I guess the old Voyager is back in the game until me and the dealer have a little talk. I've been at it long enough to know stuff breaks and to give myself plenty of cushion in traffic. These "new rigs" i.e. 1/2 ton pick-ups pulling 30' 'towables' he's installing these controllers in could come back to haunt him. But I doubt he listens, he had two P3s on the shelf and about 30 of the bargain models.

[TXiceman]

I'll stick to my MaxBrake controller....wins hands down over ANY of the inertia based controllers..
MaxBrake™ - Hydraulic over Electric Variable Brake Controller

Ken

[menoble]

Originally Posted by TXiceman

I'll stick to my MaxBrake controller....wins hands down over ANY of the inertia based controllers..
MaxBrake™ - Hydraulic over Electric Variable Brake Controller

Ken

I certainly like the concept of the MaxBrake, relying on inertial forces to trigger the trailer brakes seems a little a** backwards anyway. But the installation spooked me a little, not sure I want to tinker around with my brake line plumbing.

[TXiceman]

The hydraulics system is not any problems. The small Tee and tube add very little volume to the system. I did bleed mine at the pressure transducer to be sure there was no air. The auto manufacturers try to scare everyone away from the brake system.

If you don't know what you are doding, get a professional mechanic to mount the transducer.

The Maxbrake works much smoother and more positive than the inerita controllers.

Kne

[J Birder]

I don't want to hijack the thread, but does anybody know how the Chevy Integrated Trailer Brake Control (ITBC) System works? I suspect that it taps into the hydraulic system like the Maxbrake, but I haven't been able to find any real information.

[rollondown]

The intergrated ones that Dodge, Chevy, and Ford use I believe are designed like most of the inertia based controllers.
I LIKE my P3, but I Love the Maxbrake setup. I will switch to one as soon as I can.

[richardcoxid]

A short history on brake controllers- (as I remember it)
My parents had a small single axle pull trailer back in the mid 50’s. The brake controller was a pressure operated variable 6V resister pad about brake pedal size and 1/2in thick. It was strapped to the brake pedal with HD rubber bands. This was truly a PROPROTIONAL controller i.e. Pressing the brake pedal compressed the resister and the voltage to the Rv brakes would increase. No computer or anything, just a pressure operated high amperage variable resister.
The next generation of brake controllers tapped a small hydraulic line into a brake line at the master cylinder and was snaked into the cab and connected to a small slave cylinder in the brake controller body. This slave cylinder was connected to a variable 12V resister. There again a truly proportional system. This was the system of choice for 20-25 years until Anti-Lock brakes were introduced, when the vehicle manufactures wouldn’t allow you to tap into the brake hydraulic systems. The controller manufactures came up with the problematic pendulum (inertia) type and time constant controllers.
I also had one of these time constant death traps! When you applied the TV brakes the controller slowly ramped up to max in applying the RV brakes. This means that when you were gradually slowing down the longer you had the TV brakes applied the harder the RV brakes were applied, then release the brakes and apply them again. Conversely under a panic stop the TV brakes were doing all the stopping while the RV brakes were gradually increasing.
Also about this time there was a Jordan Ultma 2020. This was operated by a small diameter shielded cable that one end was connected to the brake pedal arm and the other end connected to the controller body that moved a variable resistor to vary the voltage to the brakes. This was again a truly PROPROTIONAL brake controller, i.e. apply the brakes when going forward, reverse or even stopped and voltage was applied to the RV brakes. I understand that the Jordan was sold and the new owners stopped producing them. I had a Jordan for about 6 years until one time on 5w hook up it smoke tested itself.
The MaxBrake has a pressure transducer connected into a Hyd. Brake line. This is again a truly proportional brake controller! Press the brake pedal and the voltage to the brakes increases even when you are stopped or are backing. The small volume of brake fluid displaced by the transducer is approved for use with TV Anti-lock brakes. The Max Brake controller is available mail order only, I am not aware of any RV dealer that stocks them.
I did make a change to the instructions- Max Brake supplied a steel brake line that went between the adapter “T” and the Transducer. To me that presented two potential problems, 1- bending the steel line without kinking it, 2- vibration of the relative heavy transducer could cause the 8 inch long steel line to work harden with the potential of a resulting fracture. I had a local hydraulic hose company fabricate a length of hydraulic brake hose with the proper crimped on end fittings. I then attached a small piece of 1/8”aluminum to the firewall pinch weld and used a small “U” bolt to attach the transducer to the bracket. On my truck there are two power brake lines alongside the Master Cylinder that the transducer could also be attached to using cable ties.
BTW- I am under the impression that the Brake Smart (very similar in operation to the MaxBrake) is no longer in business.
As far as I know other than the Max Brake all of the brake controllers available today are either inertia (pendulum) operated or are time constant operated.
Max Brake is available only by mail order. http://www.plugitright.com/ and http://www.maxbrake.com/
Disclaimer- I have NO financial or other interest in “Plug-it-right” or “Max Brake”.

[J Birder]

I am not 100% positive, but as I understand it, the integrated brake controllers available in Chevy, Ford and Dodge pickup trucks also tap into the hydraulic system. Does anybody know for sure?

Joel

[Kevinc2011]

The Dodge is an Electric system! I do not think that any of the OEM systems tie into the hyd systems due to ABS systems.