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So your engine light is on. It could be nothing. Or it could be a sign that your engine is about to leave you stranded in the middle of the highway. Either way, you’re going to have to spend a stack of cash to get it checked out. Which brings you here, looking for advice on the best car diagnostic scanner, so you don’t actually have to go to the mechanic every time that godforsaken light appears.
As its name suggests, a car diagnostic tool scans and examines your vehicle for whatever is causing the problem and gives you a diagnosis directly, without the pricey middle man. Car diagnostic scanners come in both bare-bones and high-tech varieties, and no, you don’t need to be Baby Driver to use either one.
The best car diagnostic tools won’t fix your vehicle, but they can point you in the direction of where your problem may be. Using special codes (more on that later), the scanner can tell you whether you have a problem with your engine, with the battery, with the circuitry or something else altogether.
The best car diagnostic scanners are an essential tool for your car emergency kit, to let you easily and accurately get an idea of where your car troubles may lie.
What You Need to Know Before Buying a Car Diagnostic Scanner
There are a few things to keep in mind before starting your car diagnostic tool search.
OB-1 vs OB-2: There are two basic types of diagnostic scanners which are not interchangeable. OB-1 scanners are make and model-specific tools for vehicles made before 1996. In ’96, on-board diagnostic systems were streamlined so all cars had to use OB-2 diagnostics. OB-2 diagnostic scanners work with this system, so can be used for pretty much any vehicle manufactured after that year.
Code reading: After running the scanner, the unit will show you your car’s “trouble code,” which points to the problem. With the most minimalist scanners, this is all the information you get, so you’ll have to do some Googling and research — the same way you’d do for a mysterious Netflix error code, for example. More high-tech scanners translate codes into actual words, and some even provide trouble-shooting instructions and can connect to your smart phone via an app.
How to use it: With the engine off, plug in your scanner, usually under the dashboard to the left of the steering wheel. Then turn the engine on and follow your scanner’s instructions. After you’ve received and interpreted your trouble codes, you can decide if you’re confident enough to find your own parts and make the repairs yourself, or if it really does need a professional. Even if you do decide to go to a mechanic after diagnosing the problem, you’ll still be armed with enough information to avoid any possible fleecing.
