/diy/ - Do It Yourself

I have a pic related that I'm going to pair with a Bluetooth capable arduino. I can read the toggle switch easily, but im having issues with the buttons.

The connector for it has three pins and they are labeled red, black, white and increase, common, decrease respectively.

However the adapter cable that comes with it only has 2 wires out, red and black. First I assumed that I had to read it analog but the ranges I can detect are so small and unstable that I doubt this is the case. I guess my choices at this point is to cut the wires and test directly with 3 of them and hope thats the right call?