Diagnose car problems without going to a mechanic with an auto code reader. Simply plug it into the car’s computer system, then interpret the trouble code readout. Use the car code reader as a starting point Nothing can knock your day off track faster than a “Check Engine” light popping up on your dash. You wonder if you should pull over and shut off your vehicle or drive right to a shop. An engine code reader/scanner can help you make the drive/no drive decision and even help you fix the problem. It works by plugging into the car’s computer system and displaying a “trouble code.” An engine code reader/scanner is worth buying if you’re a fairly competent amateur mechanic who understands how an engine works. But it’s not a silver bullet that will always tell you exactly what’s wrong. An auto code reader give you a head start, but you’ll still have to do some detective work before you start pulling and replacing parts (more on this later). The least expensive a...