How to merge objects while keeping textures the same?

So, I have a human model that I want to rig, but it won’t work if I do it to parented objects. When I merge it with Ctrl - J, materials get mixed so grey objects are now red and yellow, and it looks like he has Ronald McDonald’s guts all over him. Help?

How are the textures mapped.
When you join objects each face maintains its original material and any UV mapped textures will maintain their UVs

Please supply a demo blend file for review


After CTRL+J:

I didn’t use a UV picture/texture map, I just put in a color from the Materials section because I’m a noob :confused:

Nevermind, I fixed the issue. Although, I do need help with rigging. Whenever the head bone moves, the head(stop sign) will bend funny, like the sides will go forward while the middle goes back, etc.

I could send a blend file for examination, but please do not spread it. It’s not supposed to be public.