General Purpose Tools

OBD II Diagnostic Scan Tool


Learn why the idiot light went on

Most mechanic shops charge half-an-hour to an hour of labor for the honor of scanning your “check engine” light. Do yourself a huge favor and buy a simple OBD II diagnostic scanner. OBD II has been standard in all vehicles since 1996. A handheld scanner will let you read the diagnostic codes*, which you can then look up on the Internet. More often than not, the fix is exceedingly straightforward e.g. replace spark plugs.

At the very minimum, you’ll have an idea of what’s going on so can decide if a trip to the mechanic is worth it. You can also clear codes for trivial issues, e.g. air in the fuel system because you forgot to replace your fuel cap.

There have been some similar wireless products featured here on Cool Tools, but I recommend a no-frills corded model. No struggling with Bluetooth pairing, Wi-Fi reception, Apple/Android compatibility, etc. Power is provided by the OBD II port itself so you don’t have to worry about batteries either. I’ve linked a model similar to the one I own, but as far as I can tell they’re all made by a few OEMs so any brand will do. Over 11 years I’ve probably saved myself hundreds of dollars for an upfront cost of about $25. Completely worth it.

*To be clear, an OBD II scanner will let you read standardized diagnostic codes as mandated by federal law. You will not be able to read proprietary manufacturer-specific codes or perform advanced functions like reprogramming the ECU.

-- Nabhan Islam 04/11/18