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What Is an OBD2 Scanner and How Does It Work?

Discover what an OBD2 scanner is and how to use it to diagnose and fix car problems before they escalate into major repairs.
Ars Technica

Scanner installed but the computer can't detect?

I just installed the new scanner. I have the scanner icon, cables properly hooked up and the green light is ON in the scanner too. But when clicked on scanner icon it says "can't find any scanner" ...