Luckily I found a way to replace the cable easily. I hope this helps others who need to replace their cable.
Note: While this worked for me and I imagine it will work for others, I can only say that this is a fix for Guitar Hero: World Tour for the Wii. Let me know with any comments if this works or doesn't work for any other systems or games.
Step 1: Build of Materials
- Soldering iron
- 6 feet of headphone cable
- Headphone jack
Step 2: Getting to the Sensor -1
- Carefully remove the pad, this should make the screw holes available.
- Remove the screws securing the kick sensor.
Step 3: Getting to the Sensor -2
Flip it over so that the wires are facing you.
Step 4: Remove the Existing Wires
Step 5: Headphone Plugs 101
The most common type of cable I could find had a stereo jack.
This is not a problem.
Both the top and very bottom part of the stereo plug (don't use the middle part) are compatible with the mono plug.
For your jack, consult the wiring diagram for your particular jack or test it with a multimeter. The second image for this step you can see how I my plug connected to the jack and what terminals were what.
Step 6: Solder the Jack to the Sensor
When soldering to the sensor, use the existing solder joints.
I left lots of wire which prevents strain on the solder joints. The extra wire I just coil up inside the sensor case later on.
Step 7: Seal It Back Up and Plug It In
If you have any wire sticking out you can probably shove it back in with the sensor.
I would recommend securing the jack so that it will stay in place and not pull on the solder joints.
Take your 6 feet of headphone cable and connect the kick peddle back into the drum unit and you should be good to go.