Why is my 2013 GMC Terrain backup camera not working?

If the backup camera on the vehicle is not working then You should check a few things. Make sure the connection between the camera and the info display is not severed, and make sure the wire giving it power is not bad. The camera could also have been damaged by road debris. More likely than all of that however is a bad fuse, which is easy to fix. To get to the fuse box look to the left of the steering wheel look for a small seam or crack along the dash. Using a screwdriver or prybar You will want to pop this open. On the inside, You will find a bunch of fuses. On the back of the panel that You pulled open, You will see a diagram that will show You what each of the fuses is for. If this is not on the back of the panel then You can also find it in the owner's annual for the vehicle. Once You have figured out which fuse You need simply pull it out. The two sections that stick up should be connected by a thin strip of metal. If this has been broken then the fuse is no good and will need to be replaced. If this strip is there then the fuse is fine and can be popped back in. New fuses will cost You about 10 dollars, so they are pretty cheap.