As indicated by Schumi OBDII was mandatory in the US beginning with the 1996 model year. There were a few cars that got it early in 1995 MY. Of the MB stable, only the 201 chassis got it in '95.

I'm only familiar with the diagnostic system on the 124 chassis, but I expect that your car has a system unique to the Bosch KE injection system. There are only 10 codes and they are read via duty cycle from the ignition module diagnostic connector.

There are other diagnostic codes that flash a code, but they are not engine related. I would do some research here to ensure that this is correct for your car.

Do a search on maybe; diagnostic codes, check engine or DTC.

Good luck and Merry Christmas,