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Q: Warning light on

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The Check Engine light is on.

A: Hi, the Check Engine Light turns on when th...

Hi, the Check Engine Light turns on when the car's computer detects a fault somewhere. While you are driving the car, the computer is constantly checking all of the signals coming from the sensors throughout the vehicle. The computer knows what the values should be at any given time and if it detects values outside of the norm, it will trip the Check Engine Light and set a DTC, or Diagnostic Trouble Code. A certified technician, such as one from YourMechanic, would be able to hook up a scan tool to the car and read the DTC to help diagnose the your Check Engine Light. While the Check Engine Light is mainly used to make sure the engine is working as efficiently as possible, it can indicate if there is damage somewhere so it should be looked at soon.

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