What Check Engine light?
And now to the car's health report. The site indicated that the car's Check Engine light was on, which it was not. At the same time, the site reported no primary or secondary engine error codes. It showed that there were 618 technical bulletins available for the car, and three safety recall notices. Probably the most useful part of the health report was a box showing whether the car was ready for a smog check. This indicator does not mean it would pass a smog check, just serving to show if all systems were operating as they should be. For this car, the site showed it was not ready for a smog check because it thought the Check Engine light was on.
The Diagnosis tab on the CarMD site revealed slightly more detailed data, again showing the Check Engine light as being on along with a list of different sensors, such as misfire and oxygen. All of the sensor checks were shown as being completed without errors.
The list of 618 technical bulletins was of little use for a casual user, as each bulletin costs $2.99 to view, although there is an option to purchase a membership to view all the bulletins. The safety recall messages were over minor issues, such as making sure a battery cable clamp was properly tightened.
The CarMD Vehicle Health System worked very easily, and showed its results quickly on a well-formatted Web site. However, I find it troubling that it showed the Check Engine light as being on. It is possible that the warning light was burned out on the car, but CarMD found no error codes to back up a lit Check Engine warning. Likewise, CarMD gave no information as to what to do about the apparent problem, and it offers no features for resetting a Check Engine light.
Beyond that performance issue, the information CarMD provides might come in handy, but only if you don't trust your mechanic, the idea being that you could point out to the mechanic the problem area that CarMD identified. However, it would probably be best just to find a mechanic you do trust rather than fight over diagnostic issues.
DIY types and modern shade-tree mechanics would be better served looking at the, which costs less and delivers more functionality.