The bulb chart printout is very helpful.
As mentioned in my last post, the values on the bulbs (the few that are legible after cleaning, as many are printed on instead of stamped) cannot be trusted. A prior owner bowdlerized them, and I have to reestablish baseline values.
The backup and signal values (15W and 21W respectively) make sense. I'm less confident about the parking and stop light values. Here's why:
Last year a parking light burned out (a miniature bulb), and I spent over an hour at the dealer determining what that lamp is supposed to be (I found a 2W bulb installed -- the prior owner strikes again!). IIR, I ultimately found the correct value in a printed 190 sedan parts book, that car having a very similar taillight cluster. This became MB p/n 072601-01290066, and what was handed me was an Osram 0007-n8A, clearly stamped 14 watts. No, I didn't believe it either (14 watts in a bulb this small?) so I measured its cold resistance, which is 9.5 ohms. That works out to about 15 watts at 12 volts.
Now, *if* MB sold me the right bulb (at almost 4X what my aftermarket guy gets, but I'm paying for the information), then the stoplight should be at least the same value, as you wouldn't want a stoplight at about 1/3 the wattage of the parking light. You'd want an 18W or 21W stop light if the parking light is 14 watts. (Five watts seems really low for a stop light, in any event . . .).
Two asides. First, the aftermarket guy thought these miniature parking lights were 4W bulbs, which is what was printed on the box they came in (branded "Jahn," I think). We took one out, and it was stamped 12V14W and measured the same 9.5 ohms as the Osram. He was quite surprised (and he's specialized in MB parts for over twenty years). Second, I tried to get taillight info from the local dealer (Phil Smart in Seattle) and they really couldn't be bothered (they even claimed they don't have tail light bulbs in stock). They used to try to help, even a year ago, but I guess those days are over.