The 10 Best OBD2 Scanners

We spent 43 hours on research, videography, and editing, to review the top choices for this wiki. Back in the day, a good mechanic could tell you what was wrong with your car by simply listening to the engine. Not any more. Today’s vehicles contain sophisticated electronics that require onboard diagnostics to figure out. At least with one of these OBD2 scanners you’ll know what’s wrong before taking it to the shop or having a shot at fixing it yourself. When users buy our independently chosen editorial picks, we may earn commissions to support our work.

10. ScanTool 425801

The ScanTool 425801 has a USB attachment to plug directly into your computer, so you don’t have to worry about any pesky handheld unit to break. It can be wrapped up and stored in the glove box, too. Those who don’t have a laptop, though, cannot use this model.

  • Free license key for obdwiz software
  • Access graphs logs and export data
  • Free lifetime software updates

Brand ScanTool
Model 425801
Weight 4 ounces
Rating 3.7 / 5.0

9. BAFX Products 34t5

The BAFX Products 34t5 works on all US-based vehicles from 1996 and later. It is a cost-effective choice with its super low price point, yet it is still dependable and accurate, and has no problem clearing diagnostic trouble codes.

  • Works with most android obd apps
  • Transmits real-time rpm data
  • Bluetooth connection is inconsistent

Brand BAFX Products
Model 34t5
Weight 3.2 ounces
Rating 3.9 / 5.0

8. Foxwell NT301

The Foxwell NT301 has a tile-based layout similar to most tablets and smartphones, so many users will find the navigation and operation familiar, even if they have never used one of these devices. It works on American, European, and Asian cars.

  • Can check emission status
  • Powered by the vehicle
  • Doesn’t work on heavy-duty trucks

Model NT301
Weight 10.4 ounces
Rating 3.6 / 5.0

7. ScanTool 427201

The ScanTool 427201 lets you turn any Android or Windows-based phone or tablet into an automotive diagnostic tool, and features hacker-proof technology. It is safe to leave plugged in without draining the battery, so you don’t need to lift the hood to check diagnostics.

  • Free firmware updates
  • Can be installed in just 3 minutes
  • Supports eobd and jobd too

Brand ScanTool
Model 427201
Weight 5.6 ounces
Rating 4.5 / 5.0

6. Autel AL519

The Autel AL519 provides state emissions readiness checks and drive cycle verification at the press of a button. It can read and record live O2 sensor data, and display freeze frame data and VIN information on its large TFT color display.

  • Provides audible diagnostics cues
  • Can save a data report for printing
  • Comes with a storage case

Brand Autel
Model AL519
Weight 2.1 pounds
Rating 4.8 / 5.0

5. Launch CRP123

The Launch CRP123 offers extensive vehicle coverage, including Asian, European, and American cars, as well as multi-language support, so no matter where in the world you are, this useful model will come in handy. It can check your engine, transmission, and more.

  • Intuitive user interface
  • Comes with a usb cable
  • Displays 24 different data streams

Brand Launch
Model 301050116
Weight 1.7 pounds
Rating 4.0 / 5.0

4. Lemur Vehicle Monitors BlueDriver

The Lemur Vehicle Monitors BlueDriver can read or clear trouble codes when the check engine light comes on, so you can avoid wasting money at the mechanic’s shop. It also conveniently sends all of the data to your iOS or Android device.

  • Can perform a smog check
  • Can be left plugged in at all times
  • Displays fuel trim data

Brand Lemur Vehicle Monitors
Model LSB2
Weight 1.6 ounces
Rating 4.3 / 5.0

3. Innova 3150f

The Innova 3150f is easy enough for home DIYers to use, but powerful and durable enough for professional use. It provides step-by-step instructions for resetting most codes in 1996 or newer vehicles, and it also includes a battery and alternator tester.

  • Easy-to-use hotkeys
  • Live customer support line
  • Can upload data to laptops

Brand Innova
Model 3150f
Weight 1.4 pounds
Rating 4.8 / 5.0

2. Ancel AD310 Classic

The Ancel AD310 Classic is a budget-friendly option that can help you quickly determine the cause of your vehicle’s check engine light, so you can fix the problem and reset the code. The LCD screen features bright white backlighting and adjustable contrast.

  • Comes with two-and-a-half foot cable
  • Simple four-button operation
  • Doesn’t require batteries

Model AD310
Weight 12 ounces
Rating 4.7 / 5.0

1. Autel MaxiCom MK808

The Autel MaxiCom MK808 is a cutting edge model that can perform a full systems diagnostic check and also display live data with pinpoint accuracy. The large 7-inch touchscreen makes it easy to read and allows for user-friendly navigation.

  • Responds quickly to inputs
  • Built-in wi-fi for software updates
  • Programmable electronic keys

Brand Autel
Model pending
Weight 5.7 pounds
Rating 4.9 / 5.0

A Brief History Of OBD

On-board diagnostics (OBD) is a system that relies on sensors and computers in your car to display vital information about how your car is operating. In its earliest days, OBD took the form of cooling system gauges, tachometers, oil pressure gauges, and fuel level indicators to give us basic information about a car’s condition. Nowadays, OBD systems can tell you about everything from crankshaft and camshaft position to manifold pressure to ignition misfires.

Computerized OBD systems started coming online with Volkswagen’s fuel injected models as early as 1969. These early versions were very basic and would illuminate a malfunction indicator if there was a problem, but they didn’t provide any useful diagnostic information about the actual nature of the problem. Later on in the early 1980s, General Motors began to implement a computerized assembly line diagnostic link (ALDL), which was actually capable of reading out error codes. New OBD2 systems and scanners use a digital communication port that relies a series diagnostic trouble codes, which identify the problem so it can be found and fixed quickly.

In 1991, the California Air Resources Board (CARB) instituted new regulations that required every new automobile to have an OBD1 system. These initial systems weren’t standardized and each car manufacturer used its own connectors and data link protocol. In 1994, the Society of Automotive Engineers (SAE) recommended a standardized connector and data link protocol for all OBD systems and this became what is now known as OBD2. At the same time, CARB required that any car manufactured from 1996 and onward have the standardized OBD2 system installed and the U.S. government followed suit with nationwide regulations. The European Union instituted OBD2 regulations in October of 1998.

How To Use An OBD2 Scanner

Using an OBD2 scanner is actually quite simple and it doesn’t require any mechanical knowledge. That’s because OBD2 scanners don’t fix problems, they identify them so that you, or a mechanic, can fix them without having to waste time trying to figure out what is wrong. OBD2 scanners are simply a diagnostic tool. Think of it like a doctor’s visit for your car.

The first step in using an OBD2 scanner is to find your vehicle’s diagnostic or data link connector (DLC). It is a somewhat triangular 16-pin connector that looks similar to old computer monitor and printer ports. It is most often located underneath the left hand side of the dashboard near the steering column. Once found, you insert the OBD2 scanner connector, this can either be a cable attached to the scanner or a separate device that wirelessly sends the information, so it can initiate communications with your on-board computers. You will then see some kind of message like “establishing data link” or “searching for protocol.” If your screen does not light up with some kind of message, you device has not made a connection and you should try jiggling the connector or unplugging it and plugging it back in.

Next, you will have to enter your vehicle’s information, which may include the make and model, VIN number, and engine type. Each scanner will require different information depending on the device model and manufacturer. After you scanner has made a connection, you’ve entered your vehicle information, and it has booted up, you can then start searching for trouble codes. Browse through the scanner’s menu until you see something that says “trouble codes”, or just “codes”. You may or my not be presented with an option to choose from specific systems like the transmission, brakes, powertrain, etc. If you are, select the system you want to check and then you will be presented with a code. If you aren’t presented with an option of systems to check, your scanner will just immediately present you with the trouble code.

Understanding OBD2 Codes

Using the OBD2 scanner is just the first step. Next, you need to learn how to read the code you are presented with. You will be shown either an active code or a pending code. An active code alerts you to a malfunction that is keeping your check engine light illuminated. A pending code means that the OBD2 scan has failed an emission control system operation once, and if it fails again, your check engine light will be illuminated. At this point the malfunction will become an active code.

All of the trouble codes displayed will start with one of four letters. “P” is for powertrain codes and covers the emissions system, ignition system, fuel system, transmission, and engine. “B” is for body and covers power seating, seat belts, airbags, and more. “C” is chassis related and will cover your axles, brakes, wheel pressure, suspension, etc. “U” is for network and other communication related issues.

The second digit lets you know if it is a OBD2 standardized generic code or if it is manufacturer specific. 0 means it is generic, and 1 means it is manufacturer specific. The rest of the digits will identify the exact problem you car is experiencing. Since there are literally thousands of fault codes, nobody will have them all memorized and your next step will be to consult a list of OBD2 codes to find out what is wrong with your car.