Changing of mesh colors..

I have the following problem, I’d like to implement some sensors on a wheel I created some time ago, just to change the drive directions with the arrow-keys :slight_smile:

But as soon I press “p” the whole mesh turn into black and white…but the sensors work properly.
With very simple meshes, like an UV-sphere, I don’t encounter that problem…

Any help would be appreciated :slight_smile: