The light will come on for a variety of reasons. There are dozens of sensors and controls that are all connected to the computer module. When any one of these reports values to the computer that are out of spec, the light will illuminate. This is not always a bad thing. The computer will store trouble codes related to the reason the light illuminated. A technician can "read" the codes and tell you exactly what the problem is and what it will take to fix it.
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The light will come on for a variety of reasons. There are dozens of sensors and controls that are all connected to the computer module. When any one of these reports values to the computer that are out of spec, the light will illuminate. This is not always a bad thing. The computer will store trouble codes related to the reason the light illuminated. A technician can "read" the codes and tell you exactly what the problem is and what it will take to fix it.