Simulink and Arduino analog input always zero

Hi all.

I am trying to read data from a simple accelerometer using an Arduino as target hardware. I am using the "Analog input" block in simulink and get nothing but zero from the simulation. Everything is wired correctly. This is exactly what I am trying to accomplish:

https://www.youtube.com/watch?v=h1e-unxYTZU

Any help would be greatly appreciated!