Please excuse my ignorance, but I need some help.

I just acquired my first Mercedes (a 1980 240 D) today, but it came without an owner's manual. Although the car runs perfectly, I think-(it's my first diesel), a warning light under the speedometer flashes intermittently and without a discernable pattern.

It is a pale yellow, and is located between the brake and battery warning lights. The icon associated is a circle with concentric arcs surrounding the circle. Can you tell me what this means?

Also, there is a key-like switch on the dash below the instrument cluster. Can you tell me its purpose?

Thanks for the help. I have ordered a basic manual to answer these kinds of questions in the future, but I am concerned about driving the car with the warning light flickering. Should I be?

Thanks.

K Mitchell
Kmitchell@selu.edu

The warning light is probably for worn brake pads, at least it is on my 190E.

Good luck with your car!

Hello Ken:

The key looking thing is a idle adjust. When it's cold you can speed up the idle. It turns about one revolution.

H. O. Tyler
90 560 SEL
85 300 SD
83 240 D

Turning the key-like switch counterclockwise will increase the idle, and clockwise will lower the idle. I would recommend starting the car with the key turned fully counterclockwise then after it warms up once you have driven a few miles and the temp gauge begins to rise, you can back the knob back down to normal idle. The light you're seeing would be the brake pad wear indicator. It is probably coming on when you step on the brakes. The front pads have sensors in them which, when the front pads are worn to a certain point, will trigger the warning light. Very simple yet effective system. Anyhow, have your front pads (and rotors) checked and replaced where necessary. Hope this helps!


------------------
Rgds,
Aaron Greenberg
MB technician
Precision Motorcars, Cincinnati, Ohio
'67 250SE Cabriolet
'77 450SL
'80 300SD
'85 380SE
'89 420SEL
'93 300E 2.8
'74 Jensen Interceptor Mk.III
'81 DeLorean DMC12
'85 BMW 745i Turbo

Ken,

The yellow light is triggered by a wearable sensor in a strategically placed hole in the front brake pads. If you're a do it yourselfer, these are about the easiest to replace brake pads you'll ever touch.

Whether you replace them yourself, or have it done, be SURE to put in new sensors. They are only a dollar or two each, and are the cheapest insurance policy you'll ever buy.

BTW When the light comes on, you normally don't have to rush to a shop, or to buy pads, there is still a good bit of pad left. However, since you just bought the car, you don't know how long the light has been on. You should see to it soon.

Good luck,

------------------
Larry Bible
'84 Euro 240D, 516K miles
'88 300E 5 Speed
Over 800,000 miles in
Mercedes automobiles

my brake pad warning light flickers on and off inconsistenly as well but only while the car is moving. It does not come on when I apply the brakes to come to a stop.

this is on a 87 560SL I just picked up. Is the sensor bad in this case and how do I diagnose what to replace?

thanks in advance

dom chang

ps: no squealing on the brakes, stops very nicely.

__________________
D. Chang
Network Integration Engineer
MCSE, CLP, CCNA