Check Engine Light
Battery may be a BAD idea if there's a pushbutton/LED combo switch under the hood. Yes, it will reset the DTC but it also resets the radio codes in my C140. Don't know about W202s.
I personally have not looked at the 202 to know but if there is one check my page (red house) for what to do. Menu item #5 is the Diag Module.
Yes, you should see what the code is before resetting it.
Regards . . . . JimF
'94 S500 Cpe
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