Electrical problem

1995 Mercedes Benz E300D special edition 224000 mi. The last time I drove the car it started fine but started making a buzzing noise from behind drivers side dash board and I noticed that none of the gauges were working. The next time I tryed to start the car when I turned the key to preglow position it started to make the same buzzing noise. The preglow light came on and functiioned as usual but the only other lights that lit up were battery, ABS, SRS when all the lights usually lite up. After preglow light goes out and I turn key to start nothing happens. I traced the buzzing noise to the multifunction relay located behind the fuse box. I have replaced the relay with a new one. Now I no longer have the buzzing noise but the lights remain the same and the car will not start. I have strong headlights turn signals work 4 ways work battery is good. I have checked all fuses appear to be good. Where should I look next?