Have 1988 300 SEL. The first time I step on the brake pedal after starting, the check engine light comes on and won't go out until I turn the car off. As long as I don't step on the brake the check engine light will not go on. I've driven 1.5 hrs down the interstate without steppingon the brake and the light stays off, when I exit and step on the brake the light comes on.


Jim

Are you sure it is not the " Bulb burned out " warninglight?
Check all your brakelights.

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2007 C 230 Sport.

I checked, all bulbs are good.

Pull your instrument panel and make sure all the bulbs are in the right locations.
The wires for the bulbs had numbers on them from the factory.
Mike

I have the same problem.when I apply the brakes the cel comes on and remains on until I shut the engine off.as long as I don't touch the brake the cel remains off. maybe a vacuum problem? no one has touched the panel, all bulbs are good. brake fluid topped off. new rotors and pads a year ago. any thoughts?89 did not have the lockout transmission that required you to step on the brake in order to put the car in gear, only 90-91 had this .