HELP! - Air Pressure Brake Lamp Switch

[Dr4Film]

Well, I've given the Monaco Tech's many opportunities to help me out regarding this specific problem but they haven't been able to so far. Now, I've decided to hand it over to the many helpful iRV2 "Tech's" on this forum.

I am looking for a convenient location to tap into the cold side of the brake lamps for attaching my Tekonsha electric brake controller. The tech reps at Monaco said that the "air pressure brake lamp switch" would be on the firewall in the generator compartment. Well, on my coach it isn't there. And I haven't been able to find it so it may be buried under the dash and if so, it ain't going to happen.

I suggested to the Monaco tech reps to look at the wiring diagram for the roadside front compartment where there is located both the 20 amp fuse for the brake lamps and a brake lamp relay. I suggested that if I knew what the specific pin number would be for the brake lamp wire, I could easily tap into it for my purpose. It would be coming from one of the four plugs located on the outside of circuit board Monaco #2. The four plugs with multiple wires are colored black, grey, green and blue.

Would anyone have the specific wiring diagram for that compartment which holds three different circuit boards? One large one for chassis circuits and two smaller ones labeled Monaco #1 and Monaco #2 for additional chassis circuits. The specific one I need is for the Monaco #2 circuit board.

I would really appreciate all the help anyone can provide. I wish I had complete wiring diagrams for the entire coach as the ones provided in the owners manual really suck. Some of which aren't even related to my coach. It would help in troubleshooting many different problems and I am wondering now if the Monaco Tech reps even have access to those diagrams anymore.

Thanks very much!

Dr4Film ----- Richard.

[MonacoMama]

One of our members was able to get some PDFs of the wiring. (I am not sure if he wants me to mention his name.)

I will make a sticky and start adding the PDFs. The one problem is that I believe it is for 2005 and newer.

You will have to go through them as I am not sure they are labeled.

[MonacoMama]

I think this is the one you want. This one came from Robin_M's cache of goodies...

[Dr4Film]

Thanks, MM. This is the correct drawing and after viewing it, I can see where the brake lamps are pins 62A and 62B are located. However the drawing doesn't have any plug assemblies labeled on it that reference the four different colored plugs coming out of Monaco Box #2 to tap into.

I think the only way I am going to be able to accurately trace and identify the correct plug and wire is to run a very long wire from the rear trailer receptacle hooked to the pin on the receptacle that goes to the stop lamps and run it all the way up to the front compartment. Then hookup my ohm meter to do a continuity test on each pin in all four plugs, one at a time. One of those should show me continuity and that will be the wire that I need to tap into as it would be the "cold" side of the brake lamps.

Thanks for the diagram. I have saved it for future reference.

Dr4Film ----- Richard.

[MonacoMama]

I am adding many PDFs right now. Check the new thread here in Monaco

[Diplomat Don]

This page might help you. It's Homer's wiring from the Brake Switch company.

Brakeswitch, A better way to MANAGE your exhaust brake

[Dr4Film]

Thanks, Don. Unfortunately, I need to locate the brake light switch first and that's what I am having difficulty with. Everything located on the outside of the firewall has not been a brake light switch. The only thing left on the firewall is a huge black box that has a very large package of wire harnesses coming out of it. The box is well sealed and it is not going to come off. It is directly behind the driver's control area. If the switch is under the dash, it is totally inaccessible due to the space limitation. But there has to be a wire or wires that take the signal back to the brake lamps. If I could only find that wire.

I may end up taking the coach to someone else and see what they come up with. How a simple one wire connection ends up to be so difficult to accomplish.

Dr4Film ----- Richard.

[bullydogs1]

Below is an excerpt from an email that RVRon sent me for the brakeswitch...It taps right into it. This is in the front left run compartment where you expect it to be.

There is a red plug on the bottom right of the lower box. There are white wires hooked into the plug. One of the wires from that plug is labelled "137F Brake" in small black writing on the wire insulation. Once you find that, tap the red brakeswitch wire into it.

So you can thank him because he directly helped me.

[Diplomat Don]

Richard...I may still be missing what you need....but the BrakeSwitch connects to the wires that run to the brake lamps. In their instructions they tell you which wires to connect to. I know this because my lamps didn't work when the exhaust brake came on so I couldn't use the BrakeSwitch.

[Dr4Film]

Quote:

Originally Posted by Diplomat Don Richard...I may still be missing what you need....but the BrakeSwitch connects to the wires that run to the brake lamps. In their instructions they tell you which wires to connect to. I know this because my lamps didn't work when the exhaust brake came on so I couldn't use the BrakeSwitch.

Hi Don,

What you are missing is the fact that I am not connecting a BrakeSwitch to my brake lamp wires. The project I am working in is installing a Tekonsha electric brake controller so I can haul my trailer behind the coach. I need to locate the cold side wire of the air pressure brake switch for the Windsor and tap into it to hook up the Tekonsha brake controller.

No one seems to know where my brake switch is located and neither do I. I even have submitted the question to Just Answer yesterday, and haven't gotten a response.

I may have to take it to a professional to complete.

Thanks for trying.

D4rFilm ----- Richard.

[moisheh]

I am assuming your coach is air brakes only and not air over hydraulic. Normally a brake light switch is somewhere in the air line system. Usually very close to the brake pedal. Did you look under the coach in the brake pedal area. Newer Monacos have a wire for electric brakes under the dash. I dont know if they did this on older coaches. The industry standard for electric brake wiring is blue but who knows??

[Dr4Film]

Quote:

Originally Posted by moisheh I am assuming your coach is air brakes only and not air over hydraulic. Normally a brake light switch is somewhere in the air line system. Usually very close to the brake pedal. Did you look under the coach in the brake pedal area. Newer Monacos have a wire for electric brakes under the dash. I dont know if they did this on older coaches. The industry standard for electric brake wiring is blue but who knows??

The coach has air brakes, my Pace trailer has electric brakes. I have finish installing all of the necessary wiring to hook up the Tehonsha Electric Brake Controller. Red (hot) to power the controller, White (ground), Blue (goes to my Pollak receptacle at the rear to power the trailer's electric brakes), and the last wire will attach to the "cold side" of the air pressure brake switch of the coach. That is what I am looking for. Haven't found it, don't know where it is or where to look. Accessing the space under the dash is impossible. If it's there, then I won't be able to hook directly up to the switch, however there should be a wire harness that has the correct wire to tap into.

Maybe it would be easier to locate the air line part of the braking system and tap into that to install another brake light switch to use for driving the blue electric brake wire.

If there is another member that owns a 2002 Monaco Windsor and has gone through this same task, I would appreciate any advice. Thanks.

Dr4Film ----- Richard.

[Rex]

When I was looking for a connection to operate my SMI brake system in my toad, Monaco told me I needed to connect to the Brake Sig lead that goes to Monaco Box #2. I did that and it worked fine. That lead goes to the treadle valve of the service brake and a switch there. Connection to the treadle valve switch does not work but connection at Monaco Box #2 Brake Sig wire did work fine. It is the cold side and triggers a relay that turns on the brake lights.

On my coach, a 2001 Diplomat, the wires going into Monaco Box #2 were all white with the wire name printed on the wire. You may have similar wiring, but please be aware I have a different coach and wiring may not be the same as yours. My Monaco Box #2 is located in the front run bay under the driver's window on my coach.

I also isolated the SMI I was connecting with a diode.

Hope this is of some help in solving your problem.

[Dr4Film]

Possibly I am making some headway on resolving this issue.

I just finished reading an older thread of 2 years back where the poster was looking for the same thing on a '99 Monaco. The very last post suggested reading a technical bulletin from US Gear regarding the installation of their brake controller in older Monaco's. I've attached a copy of the bulletin with instructions and photo's.

After reviewing it, I have at least narrowed down the general location of the wire I need to tap into for the brake lamps. It is located in the lower right hand corner wire harness of Monaco Box #2. There are 8 wires coming from that harness. Now I need to narrow it down to wire #102. Like MonacoMamma had suggested earlier, Monaco uses the negative wire to activate the brake lamps.

Since the wires are not numbered or labeled, I now have to figure out a way to locate the exact wire #102. Since the relay's are not removable to trace the circuit and Pin #86 to the wire harness, I may have to probe each wire with a needle to locate it using my OHM meter.

Rex, thanks for your advice. With your information and what I found above may solve my problem. I will look to see if the wires are labeled but the last time I was in there it wasn't obvious to me.

Sounds like a plan, Eh!

I will re-post with hopefully my FINAL results after I have finished.

Dr4Film ----- Richard.