Recently, on my 420 SEL (W126), the left brake light went out. The other 2 work fine. The instrument panel warning light goes on the first time I step on the brake pedal, as well.

Here's the thing: I got a new bulb. Inserted it. Still does not work. Switched bulbs from other side, and STILL the left doesn't go.

So-its not the bulb. Like I said, all other lights (including the other brake lights) work fine. I'd love to fix it today: don't want to get a ticket.

Thanks.

I had a similar problem which I solved on my 300E.... The plastic housing had cracked out around the metal strip which snaps onto the back of the housing. This metal strip must be firmly snapped into the plastic housing. I epoxied mine and taped it while it cured hard. Also there are spring clip electrical terminals inside which may have to be epoxied back if the plastic slots are broken out as mine were. I really wish that plastic had a longer life when used as a structural part!! Anyway, short of buying a new tail light housing, that's about the most likely cure. BTW you did check all the fuses?? Luck to you.

DanielW

Had that same problem on my 300E, except the bulbs worked fine...the dash light came on solid during the day (headlights off) and would be okay with the headlights on.

I found that one of the metal strips on the RIGHT side (in my case) had a connection problem...I took a needlenose and twisted it into shape until it stopped giving off the false indicator.

It ended up being a non-issue when I backed into a truck and cracked the taillight lens...bought a complete assembly so the problem disappeared for good!

Make sure the bulbs you use are the correct wattage...usually embossed on the housing next to each bulb receptacle.

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