M&G brake light shows when brakes are on

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JerArdra

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Mar 3, 2005
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ALL,

If you have an M&G toad brake system here is an idea for you.

Go to:
http://midwayrvspecialties.com/

JerryF
 
Thanks Jerry. That sounds like a good thing for us M&G users to add.
 
Interesting... I have to test it but the unified gear system on my ride is supposed to do that (Alert me if activated other than by my foot)  I will have to test it some day (Easy enough to do)

BTW: Had a problem with the Unified gear system... Umbicial rubbed up against Blue Ox hitch adapter and shorted out.. Caught it and fixed it (had all the tool I needed and lots of tape)

Will have to work on making sure that does not happen again (have design idea to prevent it, very simple, called "piece of garden hose") used this method many times before.

Also, I think $99.00 is a bit much for something I could add to my car for about $2.99 if I wished

(I used to have a car where the brake light switch was a bit less than reliable, so I figured out how to sense when the brake lights came on.. Cost me $0.00 to do it that way, would cost a bit more to shine a light through the windshield however)
 
JerArdra said:
ALL,

If you have an M&G toad brake system here is an idea for you.

Jerry

I could have used it this summer. Somehow, my air umbilical line between the coach and the toad cracked. It was at one end under the spring tension relief spring and unnoticeable. Lost all my toad braking and couldn't figure out why I was having problems stopping hard.
 
Also, I think $99.00 is a bit much for something I could add to my car for about $2.99 if I wished

$99 bucks could be well spent if it save somebody from having a problem leading to an accident.  Sure it could be made at home cheaper but a lot of things we buy could.  Looks like a good thing to have if your using a M&G brake system.

We have a light on the dash that illuminates anytiime the Brake Buddy activates.




 
I'd like to know where I could buy an air pressure switch, respective air connectors, wiring and light all for $2.99. Do they provide a warranty for that price?
 
Tom said:
I'd like to know where I could buy an air pressure switch, respective air connectors, wiring and light all for $2.99. Do they provide a warranty for that price?

That's doing it the hard way,  I believe there is an easier way.  But I'd have to have an M&G system to be sure and M&G says their system won't fit on my car
 
John In Detroit said:
I believe there is an easier way.

I'd still like to understand how it could be done for $2.99.
 
Tom said:
I'd still like to understand how it could be done for $2.99.

Not 100% sure it can be, will have to see an M&G system operating to answer.

however the key is in the sensor,  Since M&G does not fit on my car, I can not say more (I had to go with unified gear system which includes back monitoring so if the brakes come on unexpectedly I'm advised quickly)
 
John In Detroit said:
will have to see an M&G system operating to answer.

You'll get to see a bunch of them at QZ John and I can see your creative juices flowing while parked in the desert  ;D

With the exception of the breakaway switch and associated diverter valve, everything on the M & G system is pneumatic. Where did you say you could buy the pressure sensor, light and wire for $2.99  ;D  If I were to do it, I'd probably hook up some wireless gadget to activate a light in the coach so I don't need to watch the rear view monitor, which is what the earlier referenced Midway system does.

This topic just gave me an idea for an illustrated article on supplemental air brakes for the forum library.
 
From jim-488, about toad brake.
[br]Date Posted: October 18, 2005, 08:20:09 AMI will try again. From Jim-488, about toad brake
    I have a friend that has M&G brake for there Hummer that they tow, work for braking very well.
    My toad brake is Vac Brake (Toad Stop). This works by the vacuum pump that is on board of the motorhome. A vacuum reservoir under hood of towed toad. When motorhome brake is applied, a plunger pulls a cable that runs through the fire wall of the toad and attached to the toad brake pedal. A light come on in the motorhome to tell me that the toad brake is working. Been working very well for the last 7 or 8 years.
    Took it off last motorhome and put it on this motorhome. This motorhome vacuum pump was far up front, so had another vacuum pump in which I put at the back of this motorhome.
    The company is Vac Brake    190 Wilson Blvd. North  Nap;es FL 34120-2073    Ph. 1-800 478 7883
    http://www.rvstuf.com        E-Mail  [email protected]    Jim-488
 
Tom said:
You'll get to see a bunch of them at QZ John and I can see your creative juices flowing while parked in the desert  ;D

I'm sure, and I can continue this then....

Till I actually see the system I'm guessing on a couple of things... As it happens, those are critical items on the "how to" list
 
If the M&G system moves the brake pedal, just hool up a wire to the brake switch and run a ight on the dash.  easy to do and cheap.  If it does not then the switch must be added under the hood and the wire brought into the dash and grounded there.

Easier said than done.

On my brakemaster we ran a wire from the towed brake switch to a LED on the dash of the MH.  Works great.
 
James Godward said:
If the M&G system moves the brake pedal

It doesn't Jim. There's an air cylinder inserted between the brake master cylinder and the boost. See photo. When the coach brakes are applied, the piston in the air cylinder moves and activates the master cylinder, thereby applying the toad brakes. But there's nothing hooked to the brake pedal and it doesn't move.

The breakaway switch actiavtes a valve to divert air from a backup air tank (reservoir) under the hood of the toad to the air cylinder attached to the master cylinder. See photo. In this situation, the brakes remain applied until the breakaway switch is reset.

Hooking up a light for a breakaway (and resulting locked toad brakes) condition is a piece of cake. But there's nothing electrical that's operated when the brakes are applied normally. So, sensing the application of brakes and/or loss of air, as in the situation Bernie described, would appear to require a pressure switch (or sensor).

Photos were taken under the hood of our Suburban. M & G installed the air cylinder and I retroactively installed the breakaway system.
 

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How is the diverter valve operated by the breakaway device? 
(Note: this is not a suggestion of any kind, I simply do not know and wish to know)
(The picture was not clear)
 
John In Detroit said:
How is the diverter valve operated by the breakaway device?

Yes John, as I said:

The breakaway switch actiavtes a valve to divert air from a backup air tank (reservoir) under the hood of the toad to the air cylinder attached to the master cylinder.

Here's a photo of the breakaway switch. As I said, detecting a breakaway condition is a breeze, given the switch has 12V on it. But, unless the toad breaks away, the switch isn't operated and there's no indication of the toad brakes being applied (or not applied) except, as Bernie mentioned, the braking characteristics of the coach change significantly..
 

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By the way, for those who have M&G brakes and no warning light system, the way to check that the brakes are working is to connect the air hose between the coach and toad, but not the tow bar. One person should sit at the coach driver's seat and depress the brake pedal. The other person should sit in the towed, start the engine and put the car in gear (either drive or reverse) and very slowly release the brake pedal. Careful, you could ram into the back of the coach (if in drive) or break the air hose (if in reverse) :mad: :mad:  If the car does move, the M&G is not working properly, the car should be immovable.
 
Tom said:
Yes John, as I said:

Here's a photo of the breakaway switch. As I said, detecting a breakaway condition is a breeze, given the switch has 12V on it. But, unless the toad breaks away, the switch isn't operated and there's no indication of the toad brakes being applied (or not applied) except, as Bernie mentioned, the braking characteristics of the coach change significantly..

That does indeed answer my question (I noticed some wires in the photo of the diverter valve and wondered if they went to the valve)

In the instant cause/effect a piece of tire tread had "tripped" the break-away switch causing application of the brakes

So, hooking a light across the diverter cylinder WOULD have provided indication.

Thus, the only other condition that could apply the brakes is failure of the diverter valve

Somehow I don't think that happens often
 
John In Detroit said:
Thus, the only other condition that could apply the brakes is failure of the diverter valve

I guess you haven't been paying attention to the discussion John  :(  We're talking about sensing the normal application of brakes, not a breakaway situation. As I said, breakaway sensing is a piece of cake. In Bernie's case he had a leak in the air hose between his coach and his toad. I previously reported having a leaking air connector at the rear of my coach and only found out about it when someone was spotting the rear of the coach as I was manouvering in reverse. Not quite the same situation as Bernie's.

Still waiting to hear where I can get a pressure sensor, bulb and wiring for $2.99  ;D
 
Actually Tom... I have been paying attention.  This is from the web site refered to in message 1 of this thread:

"I developed this alert system after an ?alligator? (piece of a blown truck tire) took out the breakaway cable between my coach and my toad, thus activating the M & G supplemental brake. It cost over $3,000 to repair the toad brakes. I drove 30 miles without knowing that my toad brakes were fully on as if the toad had broken away from my coach."

And in this case sensing the application of power to the diverter valve is all that would be needed.

Now, you are talking about another application of the light... That is something different and came AFTER I made the 2.99 comment

I do agree that since this would require sensing either air, or hydralic pressure (Did you know they make or made, hydralic brake light switches) you would have to pay a bit more... I still think 99 is a bit much though, Perhaps 29.95

Though I'm not up on the cost of brake repair on all toable vehicles, I do not recall paying more than 3 digits left of the decmil even when replacing drums and roaters on my ride.
 

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