What you'll need:

A Triwing Screwdriver
Soldering Iron and Solder
Desoldering Braid
Isopropol Alcohol
Tooth Brush
30 Gauge Wire



Step 1:
So here's an example of a broken wiimote.



Step 2:
I've used the Isopropyl alcohol and a toothbrush to scrub off all the residue flux from the board giving a clean surface to start from.



Step 3:
Use the desoldering braid to clean up the pads, try not to apply too much pressure or heat or you'll end up damaging or lifting them. The proper way to do it is to gently place the iron on the braid then slide the braid back on forth holding the other end of the braid. This is to remove any of the excess solder from the pads, also what happens is when you place too much heat and time on the joint you get something called intermetallic growth which weakens the joint.



Step 4:
At this point I would solder the LEDs on to complete the mod you're performing. If there are any missing pads use this wiring diagram to run 30 gauge to the correct points. If you've managed to damage any of the resistors (outlined in white) you'll need to replace them, they are 0402 470ohm resistors.



Step 5:
If for some reason you can't solder to the vias near the 'button 2' pad, you'll be able to run them directly to the controller.



Step 6:
If you've managed to solder everything on okay but your wiimote just doesn't turn on any more, check the board for solder splashes and solder balls that may be causing shorts.





Step 7:
Once you're sure that your board is clean, check the fuse pictured below. With a multimeter the fuse should read around 1 ohm, if the fuse has blown usually from the shorts in step 6, the fuse will need to be replace (safer) or jumpered (cheap).





Step 8:
From what I've seen the culprit to a non-functional IR sensor is mistake performing the Easy A Button Backlight Mod or the Nunchuck LED Backlight Mod. This can be verified by removing the LED from the board and checking the wiimote, once verified reperform the mod being careful not to cause any shorts. A note to remember is that the shorts maybe caused by the plastic housing pressing down on the exposed part of the LED.

Source- wiimotemods

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Hey, I will be modding your Wii soon, any idea when its getting here?