Can my my Mercedes Benz C200 1998 model be scanned when the check engine light is on?
Wednesday, December 12th, 2012 AT 1:53 PM
That's when it's supposed to be checked. There can be diagnostic fault codes stored in the Engine Computer when the Check Engine light is not on, but there WILL be at least one code when the light is on. The light must turn on when the problem detected could adversely affect emissions. That applies to about half of the almost 2000 possible codes.