Hello! I am a new member to this site. I have tried searching for my problem, but can't seem to find anything.

I have a 1993 190E 2.3 (california) with the check engine light on. Some times the light is much brighter than others, but it is always on.
Near the battery is the LED light and the little button to push, that should flash codes. When I press the button, the LED does not come on. I tried sitting in the car while a friend pushed the button, and it made the check engine light on the dash light up brightly until the button was released, but it did not flash.
Is there another way to read the codes?

The car has 116,000 miles on it, and drives well, but vibrates at idle, and hesitates when cold for the first 30 seconds or so. I bought it as an extra vehicle, and don't need it any more, but don't want to sell it with the light on.

Thanks in advnce