Brake signal for trailer brake controller

[Ivan K]

I realize the age difference but I have a relay in FRB that is controlled by ECM for Engine/Jake brake lights activation. Labeled "Engine Brake LT". Removing the output wire would stop the lights for me. You likely have some similar mechanism, just possibly harder to find and do on those PCB boards that I don't have.

[Pudgy Camper]

10 hours ago, Tom Cherry said:

DO NOT START CUTTING WIRES.  Go back to how it was supposed to be wired.  The proper way is to take the NEGATIVE switched ground.  Put in the relay.  That is what most have done.  IF I am correct….the “snip a wire” fix is a dangerous strategy….messing with the input or output of the ECM. Now, if you can locate a method on another site that is documented and folks have done it….then go forward at your own risk….or maybe someone knows how to do it and can chime in.

You have a Negative (memory as all the posts are a little fuzzy) isolated brake light (service brake or pedal activated) feed.  That is what you need to use.  It was what Richard did originally, if I remember and understand.  Finding what you THOUGHT was a positive signal, but it appears that it is coming from the ECM….programmed that way, now does not, after testing, work.

I wondered about the “found the magic signal” when you posted, but thought you might have found something that others had been searching for…and failed.  But, never say…NEVER NEVER…when dealing with a Monaco circuit.

The interactions of the ECM and the brake signals and such are complicated.  We only have, to the best of my knowledge one really “guru”….and he was surprised.  

So…. Cut and snip at your own peril.  You really need to get a copy of the Insite ECM software….then understand the working and the Input/Output of each line or circuit….and then start going through the schematics on your MH and then fully understand how it works….then “snip”…

OR…do it like originally suggested.  

That is what I know…..and what many have done….otherwise, you are probably on your own…. 

Tom, I have tried to explain in the simplest way I can and also posted labeled pictures of my findings to help others that may come across this. But I have been unable to find this 'negative' wire that others have used. Previously I thought I found it, but it turns hot 12v when the brakes are pressed. (see my pictures from 9-22). That is the wire that I'm currently using for a brake signal to my brake controller. I'm not going to start snipping wires and actually I'm thinking about just leaving everything how it is and not using trailer brakes at all. After my trip last week, I realize with the light load I tow I don't need them. All other lights and flashers work as they should on the trailer. Eventually when I get a toad I will venture down the path of a toad brake system.

Right now the issue is brake lights coming on with engine brake and activating my trailer brakes. I still want to track this down but I'm not going to put a lot of effort into it. Seems like there are a few fixes for this....some guys remove a fuse, some remove a wire and others have changed it with Cumming Insight programming. If I can correct this, I'm hoping that it will also prevent the trailer brake controller from activating with the engine brake. 

I know my findings aren't typical of what others have found and used in the past. But I have put my tester on the EXACT wire that Richard and others have used coming out of the grey harness of the Monaco #2 and discovered mine is different. Trust me, I had my fingers crossed hoping everything would be the same and match up to what others have done in the 100's of posts I've researched. I don't know if the previous owner fiddled with something, or this is just how my coach is built. After seeing the installation quality of the old UTB system, I don't have a lot of confidence in whoever installed it! That is one reason I chose to remove it and start from scratch.

[Tom Cherry]

4 hours ago, Pudgy Camper said:

Tom, I have tried to explain in the simplest way I can and also posted labeled pictures of my findings to help others that may come across this. But I have been unable to find this 'negative' wire that others have used. Previously I thought I found it, but it turns hot 12v when the brakes are pressed. (see my pictures from 9-22). That is the wire that I'm currently using for a brake signal to my brake controller. I'm not going to start snipping wires and actually I'm thinking about just leaving everything how it is and not using trailer brakes at all. After my trip last week, I realize with the light load I tow I don't need them. All other lights and flashers work as they should on the trailer. Eventually when I get a toad I will venture down the path of a toad brake system.

Right now the issue is brake lights coming on with engine brake and activating my trailer brakes. I still want to track this down but I'm not going to put a lot of effort into it. Seems like there are a few fixes for this....some guys remove a fuse, some remove a wire and others have changed it with Cumming Insight programming. If I can correct this, I'm hoping that it will also prevent the trailer brake controller from activating with the engine brake. 

I know my findings aren't typical of what others have found and used in the past. But I have put my tester on the EXACT wire that Richard and others have used coming out of the grey harness of the Monaco #2 and discovered mine is different. Trust me, I had my fingers crossed hoping everything would be the same and match up to what others have done in the 100's of posts I've researched. I don't know if the previous owner fiddled with something, or this is just how my coach is built. After seeing the installation quality of the old UTB system, I don't have a lot of confidence in whoever installed it! That is one reason I chose to remove it and start from scratch.

OK….I do realize your frustration.  So, here is a different explanation……sort of missing the forest.  BTW, I towed for almost 35k with thr UTB system that is wired into your MH….no issues.  I never messed with the sensitivity and it worked.  Your controller might be different….

Have some help you.  You need to concentrate on the two “main relays”.  There are two relays that work, I think, when you push the brake pedal.  Unfortunately you have the Bussmann block and I don’t know if you have the schematic on it.  So try this. Do this EITHER way…  Pull out one of the Omicron relays.  Use your VOM or your nice meter.  Identify the 85 & 86 terminals on that relay.  Repeat until you know which of the incoming wires energizes each relay.

NOW….Start the engine.  Have someone tap the brakes.  With your finger on the relay, feel the  CLICK. I often use a piece of 1/4” tubing (like a stethoscope) in my ear.  Find at least ONE….or maybe the second that energizes when you hit the service brake.  Identify them.

Now…engine running.  Put on the Exhaust brake. Did the light come on?  If so, have them turn ON and OFF the Exhaust brake….once you have it identified…..pull that relay.  Should have no light.  That way, you know which of the ECM’s circuits is triggering the lights.  

NOW….with the exhaust brake on….tap the brakes….sometimes that cancels the third light and ONLY the tail lights work.  Hard to say, as Monaco changed stuff.

ASSUMING that you have ONE or maybe TWO relays that “clicked or energized” when only the service brake is depressed….parallel another relay in to contacts 86 & 86.  In effect, that’s what Richard did.  Run power to 30 and then take 87 to your brake controller.  This is an isolated, dedicated signal….which is what you want  and have been trying to find ….that”s the simple way to say it and approach it.

I don’t know what else yo tell you.  Until Monaco redid the brake circuit in 2005, there was never, we all thought and that is like hundreds of owners….that there was a positive brake signal.  You find one that looked good.  OPPS….it had an exhaust brake input…

Good Luck….

 

[Pudgy Camper]

On 10/5/2023 at 10:56 AM, Tom Cherry said:

OK….I do realize your frustration.  So, here is a different explanation……sort of missing the forest.  BTW, I towed for almost 35k with thr UTB system that is wired into your MH….no issues.  I never messed with the sensitivity and it worked.  Your controller might be different….

Have some help you.  You need to concentrate on the two “main relays”.  There are two relays that work, I think, when you push the brake pedal.  Unfortunately you have the Bussmann block and I don’t know if you have the schematic on it.  So try this. Do this EITHER way…  Pull out one of the Omicron relays.  Use your VOM or your nice meter.  Identify the 85 & 86 terminals on that relay.  Repeat until you know which of the incoming wires energizes each relay.

NOW….Start the engine.  Have someone tap the brakes.  With your finger on the relay, feel the  CLICK. I often use a piece of 1/4” tubing (like a stethoscope) in my ear.  Find at least ONE….or maybe the second that energizes when you hit the service brake.  Identify them.

Now…engine running.  Put on the Exhaust brake. Did the light come on?  If so, have them turn ON and OFF the Exhaust brake….once you have it identified…..pull that relay.  Should have no light.  That way, you know which of the ECM’s circuits is triggering the lights.  

NOW….with the exhaust brake on….tap the brakes….sometimes that cancels the third light and ONLY the tail lights work.  Hard to say, as Monaco changed stuff.

ASSUMING that you have ONE or maybe TWO relays that “clicked or energized” when only the service brake is depressed….parallel another relay in to contacts 86 & 86.  In effect, that’s what Richard did.  Run power to 30 and then take 87 to your brake controller.  This is an isolated, dedicated signal….which is what you want  and have been trying to find ….that”s the simple way to say it and approach it.

I don’t know what else yo tell you.  Until Monaco redid the brake circuit in 2005, there was never, we all thought and that is like hundreds of owners….that there was a positive brake signal.  You find one that looked good.  OPPS….it had an exhaust brake input…

Good Luck….

 

Hi Tom, thanks again for the input and great explanation! I never thought of trying to track down the signal wire like you explained. I'll give it a shot as soon as I have some time.

Thanks again, Jason

[Tom Cherry]

On 10/8/2023 at 12:24 PM, Pudgy Camper said:

Hi Tom, thanks again for the input and great explanation! I never thought of trying to track down the signal wire like you explained. I'll give it a shot as soon as I have some time.

Thanks again, Jason

First…glad my “gotta teach a class this way”…over COMPLICATED post made sense….  Yes, once you figure out which relay(s) energizes when you apply the service brake pedal….then put one in parallel with it and power your “need a brake light” signal through it.

Let us know….

[Jaxpops]

is what i need in this plug to convert to 7 pin round ?

[jacwjames]

34 minutes ago, Jaxpops said:

is what i need in this plug to convert to 7 pin round ?

Yes but you will have to add a 12 volt power source.   Attached is the wires that go to my plug, which is what is shown in you photo.  When you open the PDF it will be blurry, hit CTRL5 and it will clear up.  Also attached is a diagram for the 7 pin plug,  You will have to figure out which wires are for the different funcitions.

FWIW, if you follow the wires up  into the wiring loom you will probably find a male/female connector buried in the wires.  You might be better off starting there and eliminate the other connectors.  

2002_Windsor_wiring_diagrams Tow Plug.pdf

Trailer Wiring Diagrams.docx

Edited March 30 by jacwjames

[Tom Cherry]

43 minutes ago, jacwjames said:

Yes but you will have to add a 12 volt power source.   Attached is the wires that go to my plug, which is what is shown in you photo.  When you open the PDF it will be blurry, hit CTRL5 and it will clear up.  Also attached is a diagram for the 7 pin plug,  You will have to figure out which wires are for the different funcitions.

FWIW, if you follow the wires up  into the wiring loom you will probably find a male/female connector buried in the wires.  You might be better off starting there and eliminate the other connectors.  

2002_Windsor_wiring_diagrams Tow Plug.pdf 71.29 kB · 0 downloads

Trailer Wiring Diagrams.docx 169.04 kB · 0 downloads

Read back through this topic.  You need to buy a good 7 pin receptacle. There is a link for a nice one with a side 4 pin as well.  There are some  REALLY expensive ones that REV sells….with the mating connectors that will fit.  Think $200.  OUCH.

in your case, the 6 pin, based on your year….PROBABLY has the following.

Ground

LT & STOP

RT & STOP

Park (same as Clearance)

Charging (12 VDC).  This was standard on the pre 2005 Monaco. OK…we’re up to 5.

The 6th pin may be BLANK (unused) or maybe Backup Lights.

Use a test light or VOM and sort them out,  REMEMBER….you MUST have the Ignition Switch ON for the 12 VDC charging pin to work.

You DO NOT have a “brake controller” line…..as in a Monaco put that EXTRA line in.

NOW….if a Previous Owner did have a Trailer or Towed Vehicle “wire” and they ran it all the way from the front to the rear…then YES… BUT remember, if you have electric brakes and use a standard controller, you need at LEAST a #14 wire…..for a 15 Amp service.  Based on the run, a #12 is really needed….as the voltage will drop.

NEXT UP.  The 4 pin is definitely a “Rube Goldberg” set up.  Do NOT use the BLUE connectors….they are notorious for having corrosion and also getting wet and not working.  

As Jim says….trace back the wires to where the Monaco Chassis connection is.  The downstream side (going to the receptacle) should be FINE. Use #12 wires. Use crimped butt splices.  Get a Ratcheting Crimper.  All MH’s need one on board.  Amazon sells for under $30.  Then cut and splice in your new harness at the original Monaco Harness.  Do this once…..properly….and you will never have an issue….use the wiring like I see it….you will become an expert at fixing intermittent connections….

Good Luck….

 

[Jaxpops]

Thanks Tom, where did you pick up the signal that goes to the controller itself ?

[Dr4Film]

I installed a 6-Way Trailer Tow on the rear of my Previous Windsor in addition to the 7-Way that was already there. My Saturn Vue has separate Turn and Brake Lights and I wanted to keep them separate.

I simply tapped into the Factory 6-Way to accomplish that task.

I also added a 12 VDC Charge wire to the 6-Way on the back of the coach.

The existing 7-Way had a convertor to combine the Turn and Stop lights. The only thing I added to the existing 7-Way was a Blue Electric Brake wire as I wanted to tow a 30 foot trailer or just my car.

[Tom Cherry]

3 hours ago, Jaxpops said:

Thanks Tom, where did you pick up the signal that goes to the controller itself ?

OK….this is where it gets TRICKY. The conventional “trailer brake” controllers ….the ones that send a pulsed or analog signal to the electric brakes have several inputs.  Look at the schematic.  Same for the “electronic” controllers for the Toad Brakes.  PROBLEMATICO….as my GM in Mexico would say when I started to espouse a solution.  LOL.

The Toad or Trailer controllers MUST have a POSITIVE 12 VDC…..like you would have when you follow the instructions and tap into the “rear brake light” signal or the “pedal” brake switch.  Monaco DON’T DO IT THIS WAY.  They switch the GROUND or the negative.

You have to look at the prints.  Then find the magic wire that is on the switch….Sometimes there is a separate board….and has a “diode” comtrolled signal.

What Dr4Film did was test and find a ON/OFF Negative signal or wire….  BE CAREFUL….it can NOT be the signal from the Jake Brake that lights with the center or CYCLOPS or Liddy Light….THAT will burn out the system.

SO….with ignition on and prints….find the PURE Ground (Negative) switched wire….it MUST come on and go off in sync with the pedal being depressed.

OK, then you install a relay.  Fund a Chassis stud or a good Ignition source….should be at least 15 Amps….preferably 20 A. Run that line to terminal 85 (or 86) on a supplemental Bosch 5 pin relay….then take the TESTED Negative signal to the other relay coil terminal….85 and 86 are totally interchangeable.

Also run your power to Terminal 30.  Attach a wire to Terminal 87.  THIS is now your “Brake Light” signal.  BTW….I would use my 15 or 20 A power lead and use it also to the controller….

That’s the drill.  You WILL have to run a #12 wire to the rear…..unless there was one installed by a previous owner….