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The vintage trailer brake controller is still operating perfectly! I called tech support and they gave testing information verbally. He said the test is simple:
1) press brakes and verify the engage arm moves freely with hydraulic pressure
2) connect a light to the blue wire with other side of the light grounded (he said any incandescent works)
3) slide the manual lever to verify the light turns on
He told me that the system increases amperage as the engagement progresses (which is why I only saw 12.4V at any position when I only used a voltmeter)
I plan to try a high beam bulb to see if it gets brighter as the arm moves.
One other thing I learned was the wiring:
Black wire is positive power to the system
Blue is output to the trailer brakes
Red is to brake lights
NO ground is used on the controller
There is a small hydraulic piston in the back connected to the brake master cylinder which pushes the activation arm forward when brake pressure is applied. The increase decrease screw **** adjusts engagement if the control output is incorrect for the load/pedal pressure
Sounds like an improvement over my dad's old hydraulic trailer brakes. His had a hydraulic brake unit on tongue that I think connected with a hose to truck brake line. To actually use the control you would need to hook up trailer and fine adjust to avoid locking up tires. Light bulb will only tell you that amperage is adjusting. 1960 trailer hydrsulic brake unit.
Last edited by JohnNewb; Mar 6, 2020 at 04:49 PM.
Reason: Add picture
Everything works except right brake light even though the blinker does?? Anyone cross that strange bridge? 🤔
I am replacing the 1157 sockets with new Standard S36N replacements.
Also the dome light does not turn on with the light switch. 😡
I will be finishing the new accessories soon. Below dash guage set with USB charger too LOL New horn from LMC requires a ground to the terminal but does work nicely with the steering wheel ring👍
This is the controller I was talking about. Notice the manual engagement arm on the side in case you want to increase activation independent of hydraulic pressure.
The older electric units had a manual control as well so you could brake the trailer separately on down grades. Reminded me of Lucy and Desi in The Long, Long Trailer "trailer brakes, car brakes". Back when trailers weighed more than the family sedan they towed with. Used it myself on downgrades a few times.
If your right blinker works, but the right brake light does not (assuming the left brake light does work) most likely a problem in the turn signal switch.
"Back when trailers weighed more than the family sedan" especially when the trailer is full of rocks, LOL.
If your right blinker works, but the right brake light does not (assuming the left brake light does work) most likely a problem in the turn signal switch.
"Back when trailers weighed more than the family sedan" especially when the trailer is full of rocks, LOL.
Thanks for the help. Yes the other brake light works as it should. I will dig into the turn signal switch.
Turns out the electrical part of the vintage trailer brakes works perfectly however the hydraulic piston is froze up. I did take it apart and free it up but it still doesnt move under pressure but it DOES now leak nicely! Does anyone have a new style brake controller with the accelerometer?? Do those units work correctly on these old trucks if it has no idea your intended stopping rate??
I am tearing into the switch to try to fix RT brake light not working but RT blinker does. I have it apart, any do’s or donts at this stage? Any input is appreciated!
any way to clean the contacts?
The blinkers and brakelights all now work! The assembly is easy to work on.
I built a toggle switch bank out of scrap SS and mounted it under the dash. I was having trouble finding a simple multi-toggle panel without spending over $100. Does anyone know where to find something similar to what this one is that I missed?
The springs and contacts in these old sockets no longer keep good contact to the bulb making intermittent function. The sockets can be replaced, drive them straight out the back. I put the body in the vice and popped them out with a hammer and large flat screwdriver. Notice the crack in the socket as well.
I just learned this so thought I would share for those who don’t know yet and theirs need tlc
BMC Solder and shrink wrapped for longevity This is the Standard part # Bad springs under the contacts and cracked housing Primer before reflecting silver
BMC
Chrome paint for reflection
Last edited by Red60; Mar 16, 2020 at 09:41 PM.
Reason: Forgot pic
