Good day fellow Motorhome Owners,
I want to share a project that may be of interest to other owners that tow a car behind their motorhome.
The Brake Buddy which I have is one of the more popular brake systems on the market. In fact, it has won several times Motorhomes magazine "Readers' Choice Award."
Along with the basic Brake Buddy unit, I also have the wireless Classic Alert System.
The problem with the Alert System relies on a wireless technology. This is not reliable because of the obstructions like metal, length (i.e. long motorhomes - 39 feet or longer), and "radio interference."
Unfortunately, I had a problem with the Brake Buddy that caused my towed vehicle brake damage. Note, this could have been my problem by not adjusting the Brake Buddy properly. I relied on the Brake Buddy Alert System to inform me of the operation when braking. I am not sure why or why not the alert system was not working, but it failed me.
The other problem that I have is with the COST ($119 ~ $150) of this of this relatively old wireless technology. Most electronics have come down quite a bit over time since their introduction. Just look at the price of an LCD TV now vs 10 years ago. How long has this been on the market +10 years or better?
Therefore, being a retired electronics engineer, I decided to come up with a "Better Mousetrap." With this in mind, my design goals were:
1. Reliable with good indication of an "alert" i.e. when the brake arm was activated.
2. Had to be very easy to install by anyone.
3. Low Cost
My idea was to use a standard trailer brake light to "signal" when the brake arm is activated. These lights are available just about anywhere and CHEAP!
Next, I had to find out the signal given off by the Brake Buddy's Alert Signal connections. What I found is that these terminals produced a 8 volt signal when activated. This is too low of voltage for a trailer light assembly since they use a 12 volt power source. I also wanted to isolate the signal so that the Brake Buddy's electronics would not be damaged by my system.
Therefore I decided to use opto isolation with a relay (for high current) circuit. I was going to build a simple circuit until I found a very cheap ($4.99) built module on Amazon:
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You can see the module within the plastic housing.
This would be the "heart" of the system giving me isolation and proper voltage to light the bulb or LED (+12 volts)
After selecting the tail light assembly (a side marker light using two LED's - $8 COST), I went forward with using a base (a piece of hard plastic that I had) for mounting and suction cups to attach the light assembly to the windshield.
As you can see from the above picture, I had to use nylon standoffs to allow space for the light assembly
The following picture is the completed assembly with trailer light, 12 volt power using an adapter, and signal lines coming from the Brake Buddy.
The 12 volt power comes from a simple cigarette lighter adapter. I purchased a dual adapter - one for the Brake Buddy power, the other side for the Alert System (as seen in the above picture).
After assembling the project was to TEST and QC the assembly. I installed the unit in my car and powered up the Brake Buddy and the "New and Improved" Alert System. I was astonished as how well the new Alert System worked! Every time the brake arm was activated the Trailer Light Assembly lite up!. When the brake arm was deactivated, the light went off!
Total Cost of BOM (Bill of Materials) was around $20 ~ $25 for me. Note I had some of the required items in my possession, therefore lowering the total cost. However, I would imagine that the cost would be no larger than $35 ~ $40 for everything from the start.
This project met my design goals - Reliable, Cheap, and Easy to Install (just plug in the power and signal lines).
As a final note, my motorhome has a rear facing camera that is focused on my towed vehicle. This system is intended for motorhome owners that have a rear facing camera and can monitor the towed vehicle.
Best Regards
Dutch Master
2008 Newmar Kountry Star, Spartan K2 Chassis, Cummins ISL 400HP, 2014 Chevy Captiva in tow
Linear Mode
