[VAC] Re: Brake controllers

[Jim Dunmyer <jdunmyer@xxxxxxxxxxx>]

Bob,
 In essence, the "hydraulic" brake controllers that we've been talking
about have a tiny hydraulic cylinder that is fed from the vehicle's
brake system. That cylinder controls a variable resistor to send current
to the "Brake" wire in the 7-pin connector. There may or may not
(ususally isn't) a junction box ANYWHERE, but if there is, it's not
normally at the rear. 

FWIW:, NAPA sells a real nice junction box with terminal posts that's
actually designed for this application. It's about 4 X 7 X 1.5" high,
black, with grommeted holes. I wired a long piece of "trailer" cable
(7-conductor, with various wire guage sizes) to my 7-pin socket. Mounted
the socket on the hitch frame, made a loop of cable under the truck so
wire is available to repair/replace the connector in the future, then
ran the remainder along the frame, up the LH inner fender, and into the
junction box. Used lots and lots of Ty-Raps to secure the cable. 

The wires from my "lighting isolator box" (Hoppy brand, came from JC
Whitney, but NAPA should be able to get one), the brake controller, and
the solenoid-type isolator relay (for the charge wire), plus a heavy
ground all go into the J-box. The lighting isolator gets its power from
the battery through a fuse or automatic-reset circuit breaker and is
triggered by the LH and RH signals and the taillight circuits on the
truck. This little gadget totally isolates the trailer lights from the
vehicle's so that I have no worries about overloading the light switch,
no need for a "heavy duty" signal flasher, etc. Even a direct short
someplace in the trailer or associated wiring will leave my vehicle
lights operational. 

A side benefit to this arrangement is that I make NO connections under
my truck. I've done this in the past and find it to be a trouble area in
the future as road salt and moisture do their thing. No More.

This is a bit more work than the way most folks do it, but gives me an
installation that is as close to bullet proof as it can be.

                                   <<Jim>>