Our Wii nunchuk broke. After disassembly, it was obvious that two of the wires in the connector end had broken off. I immediately did a search on the internet for information, and found useful diagrams at wiire.org. The problem I had was that the wire colors I had did not match the colors that they had posted. After disassembling both the controller and the connector, I mapped out the appropriate colors for my particular controller. If you have to repair your Wii Nunchuk, I suggest that you do the same to ensure that the wires are mapped to the correct pins. In particular, on the Wiire site, the red wire was connected to the +3V pin. However, on my controller, the red wire was connected to the clock line.

Wiimote Bus Pins (6-pin proprietary connector on Wiimote)

Looking into Wiimote (or at the exposed pins on the nunchuk connector):

_________
| 1 3 5 |
| 2 4 6 |
|__---__|

• 1 (Red wire) - +3V - (Brown on my system)

• 2 (Yellow wire) - Clk (Blue on mine)

• 3 (Red wire) - Attachment detection? (No connection on mine)

• 4 (No wire) - Unknown (unconnected at Nunchuk connector) (No connection)

• 5 (Green wire) - Data - (Red on mine)

• 6 (White wire) - GND - (Yellow on mine)

• The shield wire (white on mine) was soldered to the metal housing.

Wiimote Bus Pins (linear connector on Nunchuk PCB)

. _ _ _ _ _ _
1|_|_|_|_|_|_|6

• 1 (Red wire) - +3V - (Brown on mine)

• 2 (no wire) - N/C

• 3 (Yellow wire) - Clk - (Blue on mine)

• 4 (Green wire) - Data - (Red on mine)

• 5 (White wire) - GND - (Yellow on mine)

• 6 (Black wire) - Shield (GND) - (White on mine)

Note that the +3v was labeled on the controller board, and was the pin closest to the cable. Another way over verifying this is to note that pin 2 has no wire going to it.