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Easiest-to-Use: Ancel Classic OBD Scanner at Amazon
"It works on most cars made in the U.S. after 1996 or made in the EU or Asia after 2000."
Best Warranty: OBDLINK MX at Amazon
"Unlike most other units that feature one- or two-year warranties, you get three years of repair and replacement guarantees."
Best Built-In Library: Foxwell NT301 Car OBD2 Code Scanner at Amazon
"Automatic VIN acquisition helps this scanner grab manufacturer specific codes."
Best Value: NEXPEAK OBD2 Scanner at Amazon
"There’s lifetime free data updates, a built-in memory card to store diagnostic data, and you can even upload to computers."
Best Budget: Veepeak OBDCheck VP39 at Amazon
"The unit offers check engine light functionality, freeze frame options, I/M readiness, and VIN call-up capabilities."
Best for Smartphone Users: BlueDriver Professional OBDII Scanner at Amazon
"This small sensor, once installed, transmits codes, errors, and information via Bluetooth to the BlueDriver app."
Most Compact: Udiag OBD2 Scanner at Amazon
"This scanner is small, but mighty, making it very portable and compact enough to hold and operate using only one hand."
Best Splurge: Wsiiroon Professional OBD2 Car Code Scanner at Amazon
"The extra-large color LCD screen shows you the codes directly and the unit provides audio feedback."
The Ancel Classic OBD Scanner is easy to use even for those who are not comfortable working on cars. It works on most cars made in the U.S. after 1996 or made in the EU or Asia after 2000 and supports multiple languages, including English, French, Spanish, Russian and German. The large LCD display has a white backlight to make it easy to read even in dim lighting. If it turns out that your code isn’t serious, this device can turn off that annoying check engine light. The scanner comes with a 2.5-foot long well-insulated cable that connects with your car’s OBDII data link connector; no other battery or charger is required as it powers up through that link. A three-year warranty means you can rest easy choosing this scanner.
With its rich feature set and ease of use, the OBDLINK MX could have earned a lot of spots on this list. It will work with virtually any vehicle sold in the US since 1996, including light trucks, but excluding electric vehicles. Once installed, it transfers data via Bluetooth and there’s a smartphone app that works seamlessly with the device to automatically allow you to look up much of the code output the MX offers, even if it’s specific and cryptic. There’s also a “heads up display” mode on the app, so it will double as a meter if you have a phone holder for your car. This is great, so you don’t need to buy a separate HUD display. There’s smart BatterySaver tech built in that detects when you shut off your engine and shuts off the Bluetooth, but when you reconnect via Bluetooth — by bringing your phone within range — it will automatically turn the receiver back on. Additionally, you can connect the unit to other third-party apps, so if you don’t like the one built by OBDLINK, you’re all set. OBDLINK claims that the Bluetooth transfers about 4x faster than most of the competitors. But don’t let all those other features distract from the best one here; unlike most other units that feature one- or two-year warranties, you get three years of repair and replacement guarantees.
Like some of the other options on our list, the Foxwell NT301 Car OBD2 Code Scanner can quickly read and erase engine fault codes, but it also provides on-screen code definitions and a built-in code look-up library to quickly and easily allow you to determine the cause of your check engine light without needing a separate manual or any other reference. Automatic VIN acquisition helps this scanner grab manufacturer specific codes, too. This scanner also shows live vehicle sensor data in text and graph format, which gives you additional tools to figure out what is going on with your car. The full-color screen is easy on the eyes and the red-yellow-green LED indicator helps you quickly check emission monitor status and catch intermittent problems too.
This error scanner from NEXPEAK has all the core features you look for in a unit: error code lookups for check engine lights, a monitor for MIL codes, and even the ability to check the battery health of your car. It hooks up with the standard six-pin connector and it’s compatible with basically every U.S. car made since 1996, so chances are, your vehicle is compatible and covered. There are 10 standard OBD2 modes including read/erase fault codes, auto VIN acquisition, EVA testing, advanced onboard monitoring, and more. The 2.8-inch color screen offers a bright interface for running tests and reading codes, and with an STM-32 chip operating the unit, it runs a good deal faster than many of the competitors. There’s lifetime free data updates, a built-in memory card to store diagnostic data, and you can even upload to computers — though the manufacturer states that it will only work with Windows.
Veepeak has a few different offerings at the low end of the engine code reader range, but few options are as affordable as the OBDCheck here. The VP39 works with most OBDII protocol vehicles, so you’ll be covered with most U.S. vehicles after 1996 and most Canadian vehicles after 1998. The unit offers check engine light functionality, freeze frame options, I/M readiness, and VIN call-up capabilities. The unit also features a bright DTC-definition display and an easy-to-use interface. There are some shortcomings, as it doesn’t read ABS, airbag readiness, or oil change lights, but that's to be expected at such a price point. What is great is you get a 30-day money back guarantee if you aren’t satisfied with the readings, and there’s even a one-year warranty protecting against manufacturer defects.
The BlueDriver OBDII Scanner isn’t exactly the cheapest option out there, but seeing as it’s aimed at those who want more professional readings than you can get from all-in-one units, that’s to be expected. This small sensor, once installed, transmits codes, errors, and information via Bluetooth to the BlueDriver app. This app is the centerpiece of the whole unit, as it’s one the most beautifully designed and full-featured pieces of software we’ve seen. You can take all the requisite actions like calling up codes, searching them, and even setting the app into HUD mode to treat it as an onboard meter. What’s extra interesting about this is the 24/7 support, meaning that you can actually get in touch with an actual human if you need more information on a particular reading. You can even have the app generate repair reports on-demand that are compiled and verified by certified technicians. These repair reports are pulled from a database over 6.6 million vehicle-specific diagnostics, so chances are, you’ll be able to pull one up for your specific vehicle.
The Udiag CR600 engine error code reader can read engine fault codes, clear trouble codes, turn off the “check engine” light, as well as view both live and freeze frame data for all OBDII-compliant U.S., European and Asian vehicles. This scanner is small, but mighty, making it very portable and compact enough to hold and operate using only one hand. The rugged rubberized housing gives it a good grip and protects it from bumps and spills. The Udiag scanner comes in red or blue instead of a neutral color, so you can show off a little personality with your choice, too. The code definitions can be displayed in multiple languages, including English, French, German or Spanish.
If you are a car enthusiast and can handle fixing a lot of your own car problems, this little scanner will quickly pay for itself with all the trips to the mechanic you’ll be able to avoid. The Wsiiron Professional OBD2 car code scanner features an array of diagnostic functions, including reading and clearing trouble codes, query freeze frame data, reading dynamic datastream, O2 sensor testing, VAP system testing, onboard monitor testing and more useful options.
It can display information in English, German, French, Spanish, Italian, Dutch, Russian or Portuguese, and it’s powered directly by the OBD2 data link connector in your vehicle with no additional devices, chargers, batteries or other cords required. Red-Yellow-Green LED indicators allow you to easily determine whether your vehicle meets emissions standards, too. The extra-large color LCD screen shows you the codes directly and the unit provides audio feedback and LED indicator lights to help you understand the trouble code’s status.
Ease of use - If you’re just getting into cars and haven’t had a car code reader before, it’s probably a good idea to purchase one that is simple to use. These scanners can have pretty advanced functionality, so it’s important to find one that isn’t too confusing and will help you figure out what’s wrong with your vehicle without too many steps.
Price - Car code readers can come in at many different price points. It’s important to keep in mind the features you need to get the best value for your money. If you know you’re going to be using the reader a lot, though, it may be worth it to spend a little extra to get the bells and whistles of the fancier devices.
Codes and sensor readings - What kind of codes—manufacturer, generic, etc.—and vehicle sensor readings do you need your reader to be able to interpret? Make sure you choose a model that's compatible with your particular car.