I have a Mercedes Benz S320 CDi W220, 2001 51 Reg. All of a sudden the Horn, Drivers Elec Seat, Heated Seat, Windows Folding Mirrors, Elec Mirrors stopped working along with the Airmatic suspension, P

Fuses on both sides of the Engine bay have been checked Fuses Under Drivers Rear Seat been checked Iv changed the Battery in the boot as was running low and I have changed the Passenger side SAMs Unit. No change to car even after SAMs unit was changed, also after using a tester I found the none of the 40 & 50amp fuses had any power :oS Please Help...