Negative Switch Brake Wiring & Electric Brake Controller Help

[FOSJ]

I'm attempting to add an electric brake controller onto my 05 Monaco Knight. Thought I had it 'made in the shade' when I found the 4-wire pre-wired wiring harness under the dash marked "Ignition, Ground, Brake & Trailer Brake". But noooooooooo...when I tested the plug what did I find? The Brake lead was hot prior to pressing the brake and cold when the brake was depressed. So I began to research the US Gear website (Monaco tech support had told me the RV was pre-wired for US Gear controller). I saw a comment that stated "some late model Roadmaster chassis’s use a "negative" switched air switch".

Does anyone have experience with this type of setup? Is there an alternative site where I could connect to the brake?

I've got an email into Monaco Tech Support, but thought I'd try here as well.

Thanks

[Rex]

For the type controller you are talking about (non US Gear) you use the Brake Sig lead which you can pick up on Monaco box 2 in the front run bay under the driver's window. See the attached picture. The blue connector is where I spliced into the brake sig lead. I put a diode in the line to my controller and I think a relay to isolate the controller from the coach.

[Gutter Man]

I would like to put a controller in my 05 HR neptune 36pdq but am not able to find the plug, if there is one, behind the dash. I do have the large 7 pin plug in the back but have to investigate which wires are for what. If anyone has insight let me know.

[Land Barge]

FOSJ,
Here I'll trade 'ya..
Service Bulletin for Monaco Pre-Wired Coaches (Unified Tow Brake)
some are using the wrong pin location on the relay. I believe it's the second relay in the relay gang to the right under the driver. My first socket doesn't have a relay. DRL I think.. screwy thing is the fuse for this relay is in the rear battery box first gang, 15amp.

I used the trigger wire from the 4 wire brake controller found under the dash cover. It has 3 small gauge wires and one larger gauge (197) stepped down to fit the plug. I assumed that was the the brake actuation wire at the plug.
Brake Controller Pigtail (EC-4130) for Monaco Brand Coaches Pre-Wired with 6-pin Connector Installation Supplement for Unified Tow Brake Towed Vehicle Kit
But for the life of me I can't find the wire that goes back to the trailer plug. I've got it all to work but can't get it back to the plug. Back at the plug there is a blue wire that turns into the usual white wire then disappears.

Anyone know where I can intercept the wire that supplies the brakes? I really hate to run a wire if there is one there looking me in the face. You'd think it would be one of the larger wires..
much thanks..

2006 Monaco 40' PDQ
25' Haulmark V-nose enclosed car trailer.

[Dr4Film]

Some newer coaches have been "Pre-wired" with a harness for a brake controller, mine was not. I had to install all of the wiring for the controller.

The brake signal was picked up from the Monaco #2 box as explained by Rex. He was very helpful to me when I did my installation.

It is the small blue automotive connector seen in the second photo. That is a 12 volt NEGATIVE signal which will not work the controller correctly. The controller requires a positive signal. So what you have to do is to install a simple relay purchased from NAPA that takes the negative brake signal which then activates the relay. The relay will then send 12 volt POSITIVE to the brake controller. The wiring diagram I used came from the Unified Brake web site. I have attached it below along with some photos of the installation.

Dr4Film ----- Richard.