What is the Check Engine Light?

Posted on April 22, 2013

Exactly what is the Check Engine Light?

The Check Engine Light (CEL) is a warning indicator—it means your vehicle’s computer has determined that a component or system in your emission control system is not working properly.

The problem with check engine lights is that they identify a problem but do not specify what that problem is. To the average driver in NH, a check engine light can be a great mystery.

If one of the following lights illuminates on your dash, you may want to get a NH state inspection or at least consult an auto body shop.

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Do you know when you need auto repair in NH?

When the light comes on, one or more diagnostic trouble codes (DTC) are stored in the engine control module. These DTCs remain even if the light goes out. To address a Check Engine Light problem, these DTCs are retrieved and the appropriate troubleshooting information is followed in order to determine the problem. You will want to regularly maintain your engine and get an oil change in NH to assure it is up to standard.

Federal Test Procedure

Every vehicle manufactured in the U.S. has to first pass an Environmental Protection Agency (EPA) test called the Federal Test Procedure. This sets the acceptable limits of wear and/or failure for the emission control system. It determines what conditions will ultimately cause a Check Engine Light to illuminate.

*The CEL may illuminate to alert the drive if the emission system is faulty and the vehicle is polluting the air. A vehicle in this condition would fail an emissions inspection, a smog check, and even a NH state inspection.

Don’t confuse the Check Engine Light with the maintenance or service light. If you are ever uncertain as to whether your vehicle is road safe or not, feel free to stop by our auto repair shop in Nashua NH. Maintenance and service lights illuminate when routine services are due. They are a great timestamp for drivers to get an oil change in NH. They are usually triggered by mileage, gallons of gasoline consumed, or some other type of vehicle-use measurement.

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