Check the fuse under the dash. It will be a green mini fuse rated at 30 amps. It should be in the second row from the drivers side, around the middle of the row. It provides power to the amplifiers in the rear. Chances are the repair shop put in the amps and didn't bother to check if they work. If the radio itself still works then this might be your problem. If the fuse is still good then this is the sort of problem that needs to be physically looked over. I would say take it back to the repair shop and see what they say about gettin back in there and checking the plugs AND wiring. You may even have to go to a dealership to have it checked out. A good car audio shop would be able to help you out also, but regardless, I would contact the insurance company responsible for the repairs and let them know that you're having trouble with something that should have been fixed. They should be able to help you out with getting it done. But before you do all that... check that fuse. Hopefully it'll be that simple. | 
