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General Testing Info | Test Procedures

 

Test Procedures

How Does My Vehicle's On Board Diagnostics System Work?

Today's new vehicles have much lower emissions because they have complex computerized emissions controls. On Board Diagnostics is the computer system behind your "Check Engine" light, also known as the "Malfunction Indicator Lamp (MIL)".

You might have noticed the "Check Engine" or "Service Engine Soon" indicator light on your dashboard and wondered what it means. This little orange or yellow light is a key component of your vehicle's OBD system. The on-board computer turns on the "Check Engine" light if it detects a problem with one of your vehicle's components.

What Should I Do When the "Check Engine" Or "Service Engine Soon" Light Or Malfunction Indicator Lamp (MIL) Is On?

  


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