How To Wire a 12V Brake Light and Turn Signals

I did find a 103 one but it doesn't work
I then found a 5v 222 one and its still dont work.
So any help would be appreciated

This wire design is possible for the sabvoton72150 controler???

I was thinking buying this relay:

I have bought supposedly the 12v relay with 222 smd resister from amazon, but in the end came the 12v relay with 103 smd resister!
And test it... And for my surprise it worked!!
By the way, instead of pulling 5v throttle wire, i bought 12/24v to 5v converter.



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teklektik said:
I can recommend this opto-driver board on eBay. It has nice construction, easy connections with clear markings, and a schematic.

teklektik, many thanks for this thread of yours, superb, exactly what i needed.
the link you mention is dead.
is this equivalent / similar / good enough product (germany - eu)?
or this (china):

if yes, should i select 5v or 12v ?

i do have ca3.1, which has +5v on e-brake 3-pin connector also.

thank you

have fun

s love nia
I used a P-channel mosfet (IRF4905) for brake light in my latest light system circuit (for BBSHD). In this way, you only need to get single ebrake wire from 8-pin cable (and you should be running the mosfet from same battery with a 12V DC-DC converter). No need to splice the ebrake cables, or relays to send ebrake signal to controller - original signal is used. I'm not an electronic expert but it works, and didn't break anything in a few weeks yet.

I bought a "cable extender" for BBSHD's 8-pin cable and just spliced ebrake signal wire to connect to mosfet's gate pin, keeping the original connection.

I'm pulling the mosfet's gate to 12V with a 1M resistor, as BBSHD's ebrake signal is somewhere between 5-6 volts and mosfet maybe wouldn't turn off completely with that voltage. When ebrake is applied, the line becomes 0V and mosfet turns on. You can then use Drain of FET to activate the brake light.

I'm aware fiddling this can damage the controller, and the 6V line becomes 12V but I think 0.012 miliamps isn't going to damage anything. Anyway I'm not recommending this if you don't know what you're doing and somebody who knows better would approve this.
Awesome thread! I recently posted asking for something like this and I guess missed it before in search
I ended up getting this kit.

My bike has the same connections, so this was plug and play, mostly. I did have to create an adapter for the power source. I used the source from my existing rear light. This kit replaced that too. It's a great kit. The only issue is, that the power source is 48 volts. I believe this high voltage is making my brake sensors "stick". I never had a braking issue before this kit. I was reading that if a reed switch has too much voltage, then it could stick. This makes sense so, I bought a step down converter to create a 12 volt source. Hopefully that will resolve my issue. Great kit, all together, though. There is also a version that has waterproof connections. I'll probably get that kit for my wifes bike when her warranty is up.

UPDATE: Yes, the high voltage (48v) to this kit was making my brake sensors "stick". The step down converter resolved this issue, but the tail light won't function on 12v. The turn signals and brake light work with the 12v supply just fine. Which is ok, I have an extra 48v supply that I can use specifically for the tail light function. Everything now works great!
Does any one have a working link to a 12v opto-isolated relay with a 2.2k resistor for the brake light? Preferably US Amazon with Prime delivery or at least a website that is shipping from the US for faster shipping, but I will take any credible website. I understand enough to do the wiring, but I cannot find a 12v opto-isolated relay with a 2.2k resistor. Presently I am using a motorcycle brake light switch, which is a good option if you don't want to mess with as much wiring, but it's much harder to hide.


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