I have a 2000 S500. I lost power to the Nav. and stereosystem. I took it to the shop to see if there was a fuse blown because I didn't have a fuse chart. They said they couldn't find the problem but said they reset the system. It still didn't work and they told me that the control unit was going out and that I would need a newone. This didn't set well. I took the car home. It still had no power to the unit and I couldn'tturn it on. The next morning, I thought I would just try the power button, andmy system powered up like there was no problem. It worked for a few days and then went off again. I feel something is loose or just needs a new switch. Can someone helpme with this and give me some direction.