I have a aftermarket fan contoller and what to be notified by a led when the controller is active. Here are the leds I have.

http://www.allelectronics.com/cgi-bi...3_4_LED_.html#

I want it to light up the led when the fans have power. So Im think run a hot wire from the fan hot wire to the led and then just ground the led? Will I need a resistor or anything?

 

wont need a resistor, u culd just tap into the actual fan wires, run those to the switch, (on/off/on switch) ground and power the switch. then run the led the power side of the switch and a ground. so when u flip the switch to the on position the led will get power and come on. i believe that should work. i cant remember how i wired mine up (made a custom one with parts from radio shack) try searching, there should be a thread around here somewhere

 

here you go, try these...

https://www.camaroz28.com/forums/sho...=529484&page=3

http://shbox.com/1/fan_sw_diagram1.jpg


Heres the exact link i used. mine looks almost identical...

http://www.xious.com/camaro/

 

Actually, you WILL need a resistor for that LED. It does not not have a current limiting resistor built in and will more than likely burn out when you connect it. Use a 500 ohm (or as close as you can get) 1/2 watt resistor (don't use a lower power resistor). This will allow about 30 milliamps (safe amount of current) through the LED. If you want to make it brighter then reduce the resistance, but don't go below 350 ohms.