Rear Ac not working
 

So f course on the hottest day of the summer im taking a road trip with my friend, and they start complaining that the ac in the back isnt working. So i stopped and checked and they where right, it seems as though the fan for the rear air isnt working. I was wondering if I could get some help do you guys think this could just be a relay or fuse, if so where would they be located. Or do you think I have to replace the fan.

THanks