my overhead counsel with my temp, compass, ect keeps flickering on and off. When i hit bumps it will shut off and when i go over more bumps it will go back on... i pulled it down and the connections seem fine... the only thing i can think of is a loose ground or a loose wire going to the positive power source (fuse box?). i checked the fuse box though and it seemed ok... does anyone know where the grounding wire to this is? its a 98 extended cab with the 5.2