[Gumpy]

Do I have to replace the bulb with a halogen? Do you think the car will know the difference? My bulb socket is missing so I just soldered a bulb directly into the third brake light housing. But my my bulb replacement indicator still comes up on the dash when i hold the brakes down for a few seconds. Every single light works on the car now. But the indicator still lights up.

The indicator will light if the bulb draws a different current that the OE 21W halogen. I had the same problem and wound up replacing the socket which looked perfectly good, but wasn't! There are two types of bulbs/sockets used on the later model W140s. One uses a 20W halogen with opposing pins and one uses a 21 W halogen with asymmetric pins. The socket for the 21W bulb with the asymmetric pins is out of production, so replace it with the newer model socket (140-825-00--82) and use Sylvania 910152-012002. The newer 20W bulb is shorter and readily available. The socket cost me about $8.00 at the dealers, but can be had online for about 1/2.