How to: Check for Codes

If your car’s computer detects a problem, it will record an error code and activate the “check engine” light. You can check the computer code using a code reader. Although some newer vehicles with on-board screens may be able to display the error codes without the use of a reader. Consult your owner’s manual for more information.


Computer code reader appropriate for your vehicle

If you need to purchase a code reader, check with an auto parts retailer to determine which model is correct for your vehicle.


1. Locate the computer port.

Locate the D-shaped connector on the car. It is usually under the driver’s ...

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