I believe that MB used both one and two digit flash codes (which is flashes
separated by a pause). So it sounds like you are seeing either code two or
code 11. The document I have says that for a 1994 104 engine code two is
"Engine coolant temperature sensor circuit 1, open or short" and code 11 is
"secondary air injection system, open or short".
Now if you want to get a better idea of what might be going on, some auto
parts stores such as Autozone will check your OBDI for free.
To clear the faults do the following (copied from another site):
After eliminating a fault, the respective DTC readout must be cleared as
follows: Press the PB for 3 to 5 seconds and read out the DTC. Then within
10 secs, press the PB for 8 to 9 seconds. Then turn the ignition off for 15
secs. Note the EACH DTC must be cleared INDIVIDUALLY! If the fault has been
eliminated and its respective readout erased, the DTC will no longer be
displayed when performing DTC readout