Help with LED lighting project

[JimRoberts]

I think I've seen the wiring diagram I need on this site somewhere. What I'm looking for is how to wire a single LED to operate as both a running light and a brake light. Different resistors and a diode are needed if memory serves right. The running lights work at 9v and the brake lights at 12v. Any help with this project?

[FozzyUSN]

LED's are a current operated device. The more current, the brighter the LED becomes, up to the limit of the LED. Does the LED's come with any specifications as to what the limit of current flow might be? From there, you can compute what the resistance value should be.

[rude115]

Maybe these links will help. The LED is the diode and the resistor limits the amount of power going into the circuit. Try these and see if they help:

http://www.theledlight.com/ledcircuits.html

 

This one has the calculator at the bottom of the page:

 

http://www.rc-cam.com/led_info.htm

 

Good Luck!

[JimRoberts]

What I've got are some single lamp LED's I bought off ebay with the resistor already installed to work off 12v. I'm looking at putting several of these in the rear light/reflector that I'm currently replacing since the old one got scared and bailed out on me. There was a schematic either on this site or the venturers website that showed how to wire these where they would work as both brake and running lights. Just don't think it practical to put a bunch of lights in there and have half brake and half running. Anybody got any ideas?

[az1103]

What I've got are some single lamp LED's I bought off ebay with the resistor already installed to work off 12v. I'm looking at putting several of these in the rear light/reflector that I'm currently replacing since the old one got scared and bailed out on me. There was a schematic either on this site or the venturers website that showed how to wire these where they would work as both brake and running lights. Just don't think it practical to put a bunch of lights in there and have half brake and half running. Anybody got any ideas?

 

Don't know if this helps any, but I just got 2, 1-1/4x3-1/2 leds to replace the side reflectors on the rear crash bars. I wired them into the citcuit directly after my Back Off relay and ended up with more than expected; Not only do they work with the position lights when the ignition is on but they flash together with my brake lights and then stay at a brighter level as long as the brakes are applied. Additionally they blink with the corresponding turn signals athough in this case fairly dimly - but that's still more than I had with pure reflectors. I am satisfied with the results and plan to do the same up-front. Hope this helps....

[KiteSquid]

Don't forget Pulse Width Modulation (PWM) for LED dimming.