Texture on imported object not working

Hello,

I have a 3d model of a machine. I imported the model in 3DS Max from a .stp-file. I don't do anything else like material changes oder uv-mapping, etc.

In Unity the model is shown correctly. I have a script that changes the material of a single part of the machine. This works great if the material is color only. If there is a texture attached to the material the texture is not displayed correctly... The part of the machine just gets a average color of the texture.

I think the problem is some default mapping of the imported object? Is there a possibility to disable that? Texteure on each face, same tiling, ...?

Thanks in advance!