I'm a fan of the Tekonsha Prodigy, but I like all that electronic stuff...<grin>
<font face=\"Verdana, Arial\" size=\"2\">Would someone explain how a brake controller works?</font>
Not too complex, although my explanation may make it seem so...I'm going to assume we're talking about electric trailer brakes.
Electric trailer brakes are drum brakes, just like any car. The difference, however, is that the shoes are activated by electric solenoids rather than hydraulic slave cylinders. They're variable solenoids, also: put 14V on the solenoid and it pushes the shoes against the drums as hard as it possibly can; less voltage results in less "push" and therefore less trailer braking force. Zero volts and the shoes are retracted.
The brake controller is a device that is usually attached up front on or under the dashboard. It has four basic wires: keyed ignition power, connected to vehicle power; ground, to vehicle ground; a brake sense wire, connected to the brake switch; and trailer brake, going all the way back to the trailer brake solenoids.
What happens is that the brake controller senses when the driver is applying the brakes by the brake sense wire, and the controller then adjusts the voltage to the trailer brakes appropriately. Obviously, the controller cannot slam the full 14 volts to the trailer when you apply the truck brakes, otherwise you'd lock up the trailer brakes, so it has to modulate the voltage to the trailer. It does so with one of two major ways: time and g-forces.
The time-based ones sense when you apply the brakes and slowly ramp up the voltage to the trailer brakes to a pre-set level; you manually adjust both the max voltage level and the ramp-up speed. The g-force ones detect the longitudinal g-force of the braking and adjusts the trailer voltage appropriately: harder braking results in higher voltage to the trailer brakes. It, too, allows max voltage adjustment and an adjustment for zero g.
I've seen others in the past, such as one that tees into the hydraulic brake line, using brake fluid pressure to modulate voltage, however today's electronic controllers are much more efficient than those old dinosaurs (and significantly easier to install and use).
Regardless of which one you prefer, it's important to understand its function and how to adjust it properly, with both a loaded and unloaded trailer; for max efficiency you will be required to adjust the controller's max voltage, ramp-up, and zero-g each time you use it, and each time you change the load on the trailer, and it would not be unusual for you to adjust it during the trip for changing road conditions.
Make sense?
GA
