How to Hook Up a Diagnostic Code Reader

by Richard Ristow

Most diagnostic code readers sold are configured for the second generation On-Board Diagnostic codes, though you can buy separate scanners for codes predating the 1996 switch to OBD-II trouble codes. A car's anti-lock braking system works independently of the OBD-II codes. To access the breaking system, you will either need an ABS code reader, or a more expensive diagnostic reader programmed for all codes. Still, OBD and ABS scanners hook up to a cars in the same way.

Connect the diagnostic cable to the diagnostic code reader. One end of this cable will feature a 16-pin plug, which fits into the car's diagnostic port. The other end of the cable fits into the reader.

Connect the ABS or OBD-II's 16-pronged plug to the car's diagnostic port. This outlet is usually made out of black plastic and lies beneath the dashboard. Locations may sometimes vary, but it's usually either left, right, or directly under the steering wheel. If you can't find the diagnostic port, consult a website like, which carries an exhaustive database of outlet locations organized by year, make and model of vehicle.

Turn the scanner on. This might differ by brands and models of scanners. Some will automatically come on once they connect to the car, while others will need you to switch them on by hand.

Wait for the code to appear. In most cases, you will have to turn the car on to get the diagnostic system running. Whether you have to crank the engine or not depends on the model and age of the car.

Items you will need

About the Author

Richard Ristow has written for journals, newspapers and websites since 2002. His work has appeared in "2009 Nebula Showcase" and elsewhere. He is a winner of the Science Fiction Poetry Association's Rhysling Award and he edits poetry for Belfire Press. He also holds a Master of Fine Arts from the University of North Carolina at Wilmington and has managed an automotive department at WalMart.

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