There can be many reasons for the check engine light to be on. The best you can do is to go to service to read the engine problems from the computer. Auto Zone use to do that for free. Thry also use to have a booklet with possible problemes according the computer error mesaje
IS THEIR A LIGHT THAT FLASHES TO READ CODE UNDER HOOD?
Check Engine lights ALWAYS mean that the computer has detected a problem and you should use a code scanner to read the stored codes and figure out what's wrong.
what are some of the problems of a check engine light for 1994 E class mercedes?
How do you reset the check engine light on a 1991 mercedes Benz 560 Sel
check warning lights
There are numerous warning lights for a Mazda RX8. Some of the warning lights are for engine oil, charging system, ABS, and check engine.
A flashing check engine light is an indication of a misfire.
why does the engine light remain on after starting
It is important to pay attention to the warning lights in a vehicle. When the check engine lights are on, it indicates a problem, and it needs to be fixed.
take a battery cable off
Dashboard lights: The check-engine light glows because of a problem with the EGR valve on cars with the 2.8-liter and 3.2-liter engines http://consumerguideauto.howstuffworks.com/1992-to-1999-mercedes-benz-s-class-6.htm
sometimes when the lights blow out the fuse also blows out. check the fuse!!
If the check engine lights are on, that means that there is something wrong. A mechanic can check and tell what is wrong with the car.