Your Check Engine Light Is On. Here's How to Read It Yourself.

Your car is basically a rolling computer network, and that little “check engine” light is the car begging you to read the error message. That’s why OBD2 scanners are having a moment. You plug a dongle into the port under the dash, open an app, and suddenly your phone can pull diagnostic trouble codes like a shop scanner.

It feels like a cheat code. It can also waste your time if you buy the wrong one, or if you “clear codes” and accidentally create a bigger problem.

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