I am having some serious electrical problems with my 98 e36 m3. After driving it one day and letting it sit, it would not start back up. My personal mechanic told me it wasn't the starter, fuses, or ignition switch. He then said he would check the ignition switch relays. Three days after the mechanic looked at the car, it started to have more problems when I tried to start it. Now the radio, headlights, control lights, instrument cluster lights, and on board check control all don't work. I know the mechanic didn't do anything wrong because none of these occurred after his visit. Any help would be appreciated.