I just took my 1999 Mercedes ML430 for it's smog test. It passed emissions, and visual, but failed due to a fault code from the computer. The man said it was code 400, but did not know more unfortunately. What does this code mean, and approximately how much will it cost to fix it? I really appreciate your help in advance as things are really tight for us now.
Saturday, August 20th, 2011 AT 8:21 PM