Just for future searchers of the forum:

I searched for a DIY online and on youtube and found nothing for the w203. Thought I would share some advice for those future searchers looking for answers.

Firstly, the two map lights are the hardest part of the entire install. Use a tiny tiny tiny flat head to unseat the map light covers just enough to get the screw driver into the housing. There are 4 locking tabs for each cover and an alignment tab. All four tabs must be unseated to remover the cover. I used a fair amount of force to remove mine and did not break any tabs in the removal nor crack the cover. Once the cover is removed replace the bulb and test it BEFORE replacing the cover. The insertion of the wedge 194 LED into the map light sockets can be very frustrating. Be patient, do a shot, eventually you will get it seated properly. Do not muscle the bulbs in as this will simply push the socket up into the headliner and then youre screwed.

With the 194 installed and lighting up properly you can replace the covers. I realized that the lenses for the map lights are installed from the roof side of the headliner when the liner is removed from the car. It is impossible to get the lense covers back into the housing from the cockpit side of the front dome light. You MUST snap off two of the locking tabs used to hold the lense cover in the dome. Don't worry, the covers ride in a groove in the dome light housing and once the two tabs are snapped off you are able to get the lense to slide into this groove. There is no way to both push the four locking tabs and manuevuer into this groove with the lens at the same time. Its impossible.

The front and rear dome lights pop off with the healp of a butter knife. Pry from the FRONT of the front dome light and the clear cover will pop right off.

Pry from the FRONT of the rear dome cover and the entire assembly will fall from the headliner with the electrical connector dangling.

Replace the bulbs with the supplied units and you're good to go.

I have not yet done the vanity bulbs but will report back once I have.

I also read that several people have experienced an issue where the LEDs will actually be illuminated due to lack of resistance at the socket and that resistors were needed so that the LEDs would not be glowing 24/7.

I DID NOT EXPERIENCE this at all in my 2007 C280 4matic.

Pics to follow tonight.

 

Gosh, I guess 'tonight' never came LOL

 

I didn't get any interest. Ill do it tonight for sure lol