Hey all--I've searched and searched and come up with zero actual solutions to replacement of the reading lights in my 2009 W204 C300. They're the two little lights under the mirror, activated by switches in the ceiling, they're supposed to give a spotlight to look at something in your lap/hands while driving. I've heard they're LED, I've heard they're bulbs, I read you can remove the lens only and I read that you have to pry off the face of the mirror to reach them. The dealership shows the rearview mirror as one $950 part to replace (!!!) for two little bulbs!!!

...maybe they're LED and no one else's have burned out, and I have a short somewhere else? the amber light in the middle still works though. if anyone has any idea i'd love to hear about it! I have the mirror i found in this ebay listing (also considering just trying that, full mirror replacement from ebay, but even that feels like overkill for bulbs!)

 

I never did it, not even sure my mirror has lights.

Heres a thread on it. im guessing they removed the mirror, probably pry the plastic trim around it. carefully.

https://mbworld.org/forums/c-class-w...-changing.html

 

Oh wow, i do have lights under the mirror. Never knew. I dont even know how to turn them on. Guess it wouldnt bother me if they stopped working. But then again mine have covers and looks like tiny halogen bulbs in there.

 

ah thanks. yeah i didn't pay close attention to that post because i was looking for more of a how-to for getting the mirror open, but i think you're right, the face frame needs to be pried off to get inside.

Also, from this image it looks like they are LED's on a circuit board, not bulbs at all. maybe i have a short on the switches in the ceiling

 

ah you got the one with replaceable bulbs! there should be switches on the ceiling that activate these

 

I have the same MB..after replacing the large overhead console bulbs with LED's, thought I'd do the same for the map lights with brighter bulbs. Pried apart mirror frame as carefully as possible but still left "nibble" scars and found LED's were integral to green circuit board, too risky to change even if I wanted..desolder, resolder..yikes. If you get this far at least you could confirm 12V to the LEDs. You say both map bulbs out ? That would be pretty rare, no...so your thought that switches aren't hot may be worth pursuing.

 

How long have those lights not been working, did they both stop working at the same time? Just looking at the photo showing the inside of the mirror above they seem pretty complicated with how they function, not just a simple wire going from the switch to the light/led. I wouldn't even know where to begin testing.

I know my obd scanner has function testing of certain components. I think ive seen tests for interior lights. I know it has it for the heated mirror, I was playing around with it one day, can turn it on and off with the scanner.

I was also wondering if maybe you have the lights turned off somehow, or maybe set all the way to dim. I was reading in my operators manual but theres not much info under the interior rear view mirror section. Maybe your manual has more since you have a mirror with more functions.

I tried mine out tonight and they seem pretty handy to have, they light up the area well. I don't think I have ever turned the interior lights on manually.