European Cars
Catalytic Converters
Mufflers and Tailpipes
Check Engine Light

What causes a 1990 Mercedes 300 e check engine light to come on?

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Wiki User
January 27, 2007 5:26AM

In general, the computer turns on the "check engine" light when there is a diagnostic problem code. Use a code scanner to find out what is wrong. The computer will assist you in finding out what's wrong. Diagnostic scanners are available at most auto parts retailers.