My car stalled and would not start after going through a local car wash (battery is old). Some genius working there attempted to jump my envoy by attaching portable jump cables not to the battery but to the red and black cables of. The fuse box adjacent to the battery. As a result I have no power in the car. Seats, radio, heat. Sunroof. Interior lights, etc. I know the fuse box is in the car but am hesitant to screw with it?
Make sure the battery has a full charge, otherwise, you can't do any testing. Most autostores I deal with will come to your home, in town. They will jump your battery or bring you a new one, if needed.
If the battery has a full charge, make sure all battery connections coming and going are clean and tight. Any circuit, you have a problem with, check applicable fuses and voltage.