Flickering battery light (190E 2.6)
 

My inlaws are experiencing an intermittant flickering bat. light. I have gone over and checked the battery, reads 12.5 volts with car off, 13.5 with car running. So the alt. is charging. Whe the light does flicker, it's not at full brightness all the time. Need some help here. Could it be the regulator going? That would be nice, since it's the cheapest and easiest part to change vs. the alt.

i think the regulator would be a good start.

I had a 1990 300e with a regulator that went on the fritz. First sign of trouble was a battery light that was very dim and could only be seen at night.

There are 2 carbon brushes on the volt. reg. for the car mentioned in the first post.

- Safely elevate front end of car. Just enough to get underneath and at the bottom/back side of alternator. You may have a large plastic shroud underneath that needs to be removed.

- Back of alt. - there are 2 phillips screws. Remove and slip out of volt.reg.
New brushes are 1/2" long, so this may help you get an idea how worn down yours are.

I just went thru this with a non-MB car and it turned out to be worn brushes in the alt. Voltage readings looked ok @ idle, but still got idiot lights, especially on hard acceleration.

Take a look at the brushes on your volt. reg.

I had the same issue on my 82 300D, the light never flickered but it was so dim I didn't see it until I pulled into my garage.