I've just bought a '77 280E (my first MB) and as yet don't have a manual.
Problem is a dash light has just come on and I don't know what it is.

It is the light next to the battery warning light...two concentric circles with three dashes down each side.

Help please!

From your description I'd say it's the warning light for worn brake pads. Pull the front wheels and check the brake pad thickness. If not the front pads, check the rears. When you buy new brake pads be sure to buy new brake pad wear sensors also.

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Fred Hoelzle

I agree, it is the brake wear indicator warning.

Yep, it's the brake. You have less than a thousand miles to go and I wouldn't wait to have it fixed.

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95 R129
04 Infiniti G35.5 BS
10 X204

Thanks all for the help.

I had info from a newsgroup that said glowing yellow = brake pads; red = fluid level.

Could this be right?

Those are two different indicators...the one you specified is the brake pad wear indicator...yellow only. Unless you take your car to the track on weekends, you have just under 2 months of pad life left under normal everyday use...MB gives you plenty of time to address the issue.

The indicator with the "B" in the center means brake failure. This one is RED!

Low brake pressure due to excess air in the lines (usually due to improper bleeding) will set this light off, as well as an unexpected mechanical brake failure. You'll already know you have a problem just before THIS light comes on!!!

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car