About once every 5 months or so, one or the other of my parking light bulbs goes out and I get that same problem on my '97 E300D. I replaced the bulb the first time and about 5 months later, it went out again (passenger side). I bought another bulb, and in frustration knocked sharply on the lens with the lights on... the bulb came on and didn't fail for at least another 5 months.

Looks like I may have a problem with that socket because when I tested the bulb I had previously replaced, it showed the same resistance as a new bulb. But one or two sharp knocks on the lens brings it back to life every time.

I guess the movement of changing that bulb the first time "simulated" the knock!

__________________
Alan