looking up your car , i found a wiring diagram 126.024 your car designation s class with a 6 cylinder reading via pin id of fuel relay= pin 4 = starting valve ie when car cold it gets the starting valve injecting additional fuel , pin 8 =12 volts from x35 which is a terminal block which in turn receive power via overvoltage relay, pin 7 goes to output power to pumps and o2 sensor heating element , pin 11 is ground side of cold starting injector, pin 10 is td signal a connection from ac control unit n6 to pin 2 of n6 ac control unit , and goes to cis n3 fuel injection brain , pin 12 is crank signal from starter circuit 50 or = started solenoid, pin 2 is from brain cis n3 unsure what signal that is , pin 6 is to kick down switch, usually to disengage ac compressor under full throttle , pin 9 is key on to overvoltage relay ending at overvoltage pin 3 one leg and fuse f1 fuse 7 from ignition switch, f1 is front fuse box