Have one of those lighted fans in your computer? They are cool but the light is on when the fan is running and the intensity varies if you use a speed controller. Wish you could slow down your fan without losing your lights or just turn out the lights with out turning off the fan? In this Instructable I will show you how to do just that.
Step 1: Tools You Will Need
The tools we need are pretty basic...
A soldering iron and solder we need an old USB cable and an E-xato knife. I used a USB cable because of the size of the wires. They need to be small enough to feed under the motor housing of the fan. Just cut off the ends and remove the outside casing. This will leave you with four wires, two of which we will use. The black one and the green one.
Step 2: Getting Started
The first step is to remove the sticker covering the wiring. Once you do this locate the negative connection of the LED's. These should be marked on the circuit board of the fan.
Step 3: Testing the Lights
Next unsoldered the negative wires form the circuit board . Then temporarily soldered a bare wire to them so you can make sure that you have the right wires. Simply plug in the fan and touch the end of the wire to one of the original negative terminals to make sure the lights work. If they do then you are ready to continue wiring.
Step 4: Running a New Ground
Next feed the black wire, from the USB cable, under the motor housing and attached one end to the first wire. Be sure to tape all your connections as you do not want bare wires touching the circuit board of the fan. The hardest part of this step is stripping the wires in the middle to make the 2nd, 3rd, and 4th connection. Just strip one section at a time, then solder on the negative wire from the LED, tape the connection, then gently pull the wire through the housing so it lays flat and tuck the new joint under the motor housing.
Step 5: Finishing the Wiring
Here is the completed the wiring. The 3rd and 4th wire connects just like the 2nd wire. Once all the connections are made, run the black wire out the arm of the fan. Next solder a green wire, from the USB cable, to the original negative connection on the circuit board, and run it out the arm of the fan. Make sure these are long enough to go to the switch you want to use. Once the fan is powered up, you turn on the lights by touching the black and green wires together. These are what will connect to your switch.
Step 6: Lights On! Lights Off!
Plug your fan into your power supply and touch the green to the black and "Woopee!" we have lights! Now you can run these to just about anything you want besides an on/off switch. You could wire them into a sound controller and have them flash to your music. Use a rheostat in stead of a switch and you could control the brightness. You could even wire them to a photovoltaic switch and have them turn off in the day time. I just wired them to an on/off micro-switch mounted to the front of my computer.
Step 7: Finishing Up
Finish off the mod with a new sticker to cover the printed circuit board and your new wiring.
Now you will be able to turn the lights on and off without affecting the fan. The best part is, if you are using a speed controller on the fan, it will not dim the lights when you slow down the fan.
I hope you found this useful. If you have any questions just leave 'em in the comments and I will try to answer them.
In my next Instructable I will show you how to add some LED's to you fan.