Receiver controlled on/off switch for higher voltages
 

I'm sure this is pretty obvious for most of you, but I wanted to provide a quick "how to" for people who aren't sure how to wire up an LED light bar (or any other accessory that needs more power or voltage than the receiver can provide) and still be able to turn it on and off via the controller.

To do this you need to use a receiver controlled switch. I used one from Hobbyking linked below. You connect one side of the switch to your power source (in my case, the ESC battery plug), and connect the other side to your load (the LED light bar). Then you just tie the ground from your load (the LED light bar) to your battery ground, and plug the switch into the receiver port that corresponds to the button you want to use on your controller. Easy as that! Now when you turn the switch on, it passes the battery voltage right to the light.

Here's a diagram that illustrates how it's wired:
https://farm5.staticflickr.com/4638/...e7b3110c_z.jpg

Here's a video that takes you through the procedure:

+ https://youtu.be/_KeDSP5VlM8" title="View this video at YouTube in a new window or tab" target="_blank">YouTube Video

Turnigy Receiver Controlled Switch: https://hobbyking.com/en_us/turnigy-...-switch-1.html

I give up on trying to embed the damned Youtube code. :(

I did this with a modified circuit board out of a servo. I think I could mix the steering and throttle into the channel where I have my switch to make working turn signals/brake lights. I'm not even using this for led's, but for something else where it just needs to be on/off.

+1

I've used a sacrificial servo with channel mixing for LED brake lights that only turn on when hitting the brake:

https://www.youtube.com/watch?v=p_34oSUgtGs

As useful as the servo board is for various projects, they're generally limited to whatever voltage the servo controller can withstand, and also limited to the ESC's BEC voltage unless you also add an external BEC, but even those usually top out at 7-8 volts. Although the LED light bar I used on my Bomber has a boost/buck converter in it to allow it to work on more or less any input voltage, a lot of light bars, including my DIY light bar, needs 12V to work. That's where the relay-style switch comes in handy.

Was it even necessary to use the channel mixing on the controller for the brake lights? You could have used the y-splitter for the brake lights just like you did for the forward lights as long as you reversed the polarity of the LED.

Pretty easy for a brushed motor, but not sure how the wiring would work for a brushless setup, will you show a diagram for that please?

The motor in the car is completely irrelevant. The only thing the servo controller sees is the PWM throttle signal from the receiver. I'm saying that to hook up the reverse lights, you do it exactly as you did with your forward lights, but you turn the LED around on the servo controller's output. You can run the forward and reverse LEDs off the same servo controller, you just need the reverse one wired backwards. The servo controller uses an H-Bridge to control the polarity of the voltage to the servo motor, so when you're turning one way, the servo motor gets a positive voltage. When you turn the other way, it gets a negative voltage. So.. if you parallel that servo controller to the ESC channel like you did in your video, when you go forward, that servo motor gets a positive voltage. When you go into reverse, that servo motor gets a negative voltage. So, if you replace that motor with a couple LEDs, one wired up "normal" just like in your video, and one wired "backwards", the "normal" one will come on when you go forward, just like in your video. The one wired backwards will come on when you go into reverse.

If I can find the time, I'll try to whip up a quick visio diagram and post it. It's super easy, but I'm sure my explanation doesn't make it seem that way.

Here's a quick diagram I drew up:
https://farm5.staticflickr.com/4678/...ccd4f994_c.jpg