The Check Engine light, which is officially called the "Malfunction Indicator Lamp" (MIL) alerts you when your vehicle's OBD II system has detected a potential emissions problem. Depending on the nature of the problem, the Check Engine lamp may come on and go off, remain on continuously or flash. Of course, none of this gives you any clue whatsoever as to what might be going on.
Some people panic when they see the light, fearing their engine is experiencing some kind of major problem. But fear not, because in most instances, the problem is usually minor and is nothing that requires your immediate attention.
Here's how the Check Engine Light works. When the OBD II system detects any fault that may cause an increase in emissions, it sets a "pending code" in the computer's memory. The Check Engine Light doesn't come on yet because the system needs to make sure the problem is real and not a temporary glitch. If the same problem occurs on a second trip (under the same driving conditions), the OBD II system will then set a diagnostic trouble code (DTC) and turn on the Check Engine Light.Both the
Autel MaxiDAS® DS708 and the
Digiprog3 are good code reader tools.