Controller brake sensor wiring

emerson447

1 µW
Joined
Dec 10, 2017
Messages
1
I have a problem wiring up my new brake lever. My controller has three wires (red, yellow and green) for the brake sensors and I wish to connect up a brake lever which has with only two wires (red and blue). The new brake switch is normally open and operating the brake lever connects them together. Can I wire this up to the controller, ignoring one of the three wires coming out (red 5 volt?) or is it more complicated that that.
 
You have the right idea.

One wire on the controller, most likely the green one, is negative. The other two should be 5v positive.

At the brake handle, each handle needs the negative, and one of the 5v positive wires.

use a voltmeter to figure out which wires are positive.
 
dogman dan said:
One wire on the controller, most likely the green one, is negative. The other two should be 5v positive.
At the brake handle, each handle needs the negative, and one of the 5v positive wires.

use a voltmeter to figure out which wires are positive.
As noted in earlier post: OP's answer is 'yes'.
But - 'No!' to DD's post which can get you into trouble.

There are three wires:
  1. Gnd
  2. ebrake signal wire (appears to have +5V on it)
  3. optional +5V power used for hall sensor ebrakes only.

You must use (1) Gnd and (2) the signal wire on the ebrake end *NOT* just 'any' wire that reads +5V.

  • If you mistakenly connect (1) Gnd and (3) the +5V power lead to your ebrakes, you will short the controller 5V regulator when you apply the brakes. The bike will certainly stop but for an entirely different reason than intended....

If your wire colors are completely indecipherable, connect in turn each of the two '5V' wires to Gnd using a 1K to 10K resistor in series with your DMM set on 10ma (or thereabouts). The wire with the lowest current reading is the signal wire. (Don't forget to reset DMM function to something other than 'ma' when done of you will blow an internal DMM fuse next time you try to measure volts :( )
 
Short answer is yes.. more complicated than faking it. The last bike I worked on with Hall sensor brakes was a pain.. one piece wiring harness that made it a pain to probe and test, and the controller was looking for a specific voltage range from the cutoffs, so it wouldn't run at zero volts, i.e. disconnected, but also wouldn't run at 5 volts, so just hooking it up to source voltage was a no go.
 
Learn shit here every day.

I never heard of hall sensor brake switches, and thought he just said sensor meaning the reed switch.
 
Hi
How about correct wiring for MS-BK-1F cutoff sensor with 3 wire connector.
RED-VCC
BLACK-GND
WHITE-Signal .
Controller has 2 wire connector BLACK and RED for brake cutoff levers which I am not using since my disc brakes since they are integrated Shimano Deroe levers.
 
Back
Top