Hi all.
I'm the proud owner of a 1995 E320 that comes with an OBD I connector in the engine bay. It currently has "check engine light" and I'm trying to read the codes. I read the posting and downloaded a pdf file describing each code but I cannot find a document that specifically shows how to get the CODES out.

This is what I did so far:
1. turn the key on KOEO
2. press and hold the button for 2-4 seconds

Nothing happens. I expected the light to blink and then decode the blinks.
I also tried with KOER........ no response.
Am I doing it wrong? Do I need to make the circuit with the LED, switch and jumper wires? Or is the comm port on the MB dead?

Any help is appreciated. Thanks.