If you see a “check engine” or a “service engine soon” light in your instrument cluster; your car has stored a diagnostic trouble code. This means the computer system on your vehicle has detected a problem with the various systems it controls. Your car has many different sensors that monitor the various vehicle systems. If the trouble code light has been illuminated your vehicle enters into “limp mode” this means it is running on a predetermined program that causes poor mileage and increased emissions. An engine trouble code reader is an easy to use tool. All 1996 and newer vehicles utilize a “D” style plug-in connector that connects to the code reader. On most vehicles the connector is located at the driver’s compartment. Once the code reader is plugged in you can retrieve trouble codes the engine computer has stored in its memory. These codes are the same codes the dealer and repair shops use to replace sensors and clear codes. This video contains basic a testing procedure using an automotive trouble code scanner as a code retrieval tool. Correct computer system function is essential for your car’s engine to operate properly. Many engine run-ability problems can be related to a weak or failing sensor producing a diagnostic trouble code. Problems can range from hard cold engine starting, low power and stalling while driving. This video contains visual information designed to aid a trouble codes retrieval test using a engine code scanner.