Brake Controller

[prstlk]

I have posted several times about getting and older SAT dish to work. Solved the problem today by buying another coach. The "new" coach is a 07 HR ambasador. It does not have a brake controller for a trailer. Question is I got the dealer to throw in a brake controller but being spring their service dept is busy with no time to install it. Is there a simple conector under the dash to connect the controller. If so where do I look. If not what is the next step. I'm not afraid of pretty much anything and like DYI when ever possible.

Thanks in advance to all!

JW

[wa8yxm]

How do I do it is a loaded question since we need to know your coach AND you did not tell us the brake controller.

There are two or 3 types of brake controllers and systems, NOT all are compatiable, but assuming you are towing a TRAILER with Electric brakes I will use a very common model of progressive/purportional controller.

YOu need to make 4 connecitons under the dash

12 volt Positive
Brake light side of the brake switch
Ground
And the line (usually blue) that feeds the rear of the coach.

TO FIND the blue wire if it's already there.

Look for a blue wire at the back of the bus, May be connected to a 7pin connector if you have one of those.

If you have it, look for a blue wire not connected under dash

Measure resistance blue wire to ground. Should be OPEN

plug in trailer

Measure resistance again Should now be near short (A few ohms).

If so that's it.

Using a test lamp you can find 12 volt (Id hook to the aux terminal block if such exists) and the brake light lead,, You may be able to pick it up at the steering column connector if you have to but if you do that make sure it's not live (Blinking) with 4 way emergency flashers on.

.

For more and better information: Contact teh controller maker and dowload the installation/owner's manual... In fact you should do this in any case. Even if you have a copy of the manual in the box, DOWNLOAD one. harder to loose the hard drive.

I have downloaded manuals for most of my hardware.. and in a few cases (kitchen stuff) download was not to be found so I scanned it with my smart phone and MD-Scan and PDF'ed it and put it on the HD. Paper copies go in the Manual portfolio bag... Motor homes come with like 20 pounds of owner's manuals.

You have two identical ___, you have two identical owner's manuals.

[prstlk]

JW.... again.... On coach that sold in 07 with build sheet of 212k a factory hitch rated at 10k with a 6/8 plug on the hitch there is not a plug and play option for a brake controller no wonder we who buy and drive these things hate the manufacturers.
aaarrrrgggg
jw

[Ductape]

Running trailer braking with EB would be a good way to set your brakes on fire on a long downgrade.

[Playtime_II]

I partially agree. I would want the trailer braking if the eng/exhaust brake is actively slowing the MH. However, on long grades, constant braking on a trailer could be a problem. A better-quality controller can be adjusted for this.

Additionally, on some MHs the tail lights do not activate with the eng/exhaust brake, thus the trailer brakes would not activate.

OP would just need to be informed on how his MH is set up.

[dougrainer]

Playtime II wrote:
I would recommend NOT going to just anyone to install the controller. On a SUV/PU, YES. Your RV, NO. You RV has air brakes so you need to find a brake signal that only supplies power when you step on the service pedal. Some RVs also have their brake lights operate when the eng/exhaust brake is operating.

Here is another reason why. My 06 HR was pre-wired BUT only worked correctly with one type of controller (roadmaster I believe is what the factory tech said). The majority of controllers today use a positive brake signal to operate. My HR is pre-wired with a constant hot brake signal (until you step on the service pedal). In order to get a correct brake signal required for a P3 controller, I had to install a relay and tap into a brake signal wire in the front run electrical bay (and there were two to choose from).



If you test each of the wires for their correct operation (ONCE YOU FIND THE CONNECTOR) it can be a DIY project. Factory schematics were of little help as what was suppose to be, wasn't. Might have been a mid-yr change or change by the previous owner (to support the 'toad is braking light' they installed).

Which is why we run 2 wires. We tap into one of the rear side brake lights which is ALWAYS a 12 volt positive signal
I WOULD THINK YOU WOULD WANT YOUR BRAKE CONTROLLER TO ACTIVATE WHEN YOUR EXHAUST BRAKE ACTIVATES THE REAR BRAKE LIGHTS---YOU ARE SLOWING DOWN, IT MAKES NO DIFFRENCE WHETHER YOUR REGULAR BRAKES OR YOUR EXHAUST BRAKE IS STOPPING THE RIG. Doug

[Playtime_II]

I would recommend NOT going to just anyone to install the controller. On a SUV/PU, YES. Your RV, NO. You RV has air brakes so you need to find a brake signal that only supplies power when you step on the service pedal. Some RVs also have their brake lights operate when the eng/exhaust brake is operating.

Here is another reason why. My 06 HR was pre-wired BUT only worked correctly with one type of controller (roadmaster I believe is what the factory tech said). The majority of controllers today use a positive brake signal to operate. My HR is pre-wired with a constant hot brake signal (until you step on the service pedal). In order to get a correct brake signal required for a P3 controller, I had to install a relay and tap into a brake signal wire in the front run electrical bay (and there were two to choose from).

If you test each of the wires for their correct operation (ONCE YOU FIND THE CONNECTOR) it can be a DIY project. Factory schematics were of little help as what was suppose to be, wasn't. Might have been a mid-yr change or change by the previous owner (to support the 'toad is braking light' they installed).

[dougrainer]

Motorhomes (Diesel) do NOT have a quick connect like regular trucks for the Brake control. You should have a Roadmaster Chassis. We always run our own 12 gauge dual wire from the front to the rear, even if the chassis has the prewire to the rear. Some Diesels have a 2 wire pre wire to the rear. You still have to FIND those 2 wires in the harness at the dash area and it is extremely Difficult to do. So we run a harness from front to rear as it is quicker to do that, than it is to attempt to dig out the dash harness. We use the 2 wire to
1. Run the output brake signal to the rear
2. The 2nd wire is the Brake light signal which we splice at the rear brake light to send the signal to the brake control.
3. AT the dash you just connect the ground and the 12 volt positive to the brake controller with the 2 wires you ran.
The reason we like to use a 12 gauge separate harness is---running the BRAKE signal control 40 feet, use lose hardly any 12 volt signal strength with that 12 gauge wire. The factory harness if you can find it is usually 14 gauge and sometimes 16 gauge. Doug

[jerseyjim]

Installing a brake controller can be easy (already have a receptacle somewhere under the dash) or somewhat difficult....(splice wires and find out what does what)...then running that wiring harness to the back of the motorhome...and choosing a flat 4, round 5 or round 7 for the trailer to plug into.

My suggestion: if you have to splice wires...get a shop to do it. Not necesarilly a RV dealer....any trailer shop can do it...probably cheaper. And 100 bucks labor? IMO, well spent.

g'luck!