URGENT Help.1989 Mercedes Benz 300E Electrical problems after major car accident

Earlier this October a truck drove into the back of my 1989 Mercedes Benz 300E. The body shop only repaired the back of the vehicle i.e. replacing trunk, bumper and tail lights. Less than 48 hours later (after I picked my car from the shop) I headed home from work. As I drive into a parking lot, I slowly drive onto a speed bump. All of the sudden my car completely turns off and it has not started since. The lights and everything shut off completely. HELP