How to Choose an OBD2 Scan Tool (2020)

Posted: 5 January 2020

The worst part about vehicle problems is the unknown. You don’t know precisely what the problem is. You don’t know how long it will take to fix it. You don’t know if it’s something you can repair yourself. And most of all, you don’t know how much it’s going to cost.

One of the best tools to diagnose most issues with your vehicle is an OBD2 scan tool. On most vehicles, there’s a connector underneath the dash that is your gateway to your vehicle communications. Plugging in an on-board diagnostics scan tool can provide you with the basis of the issue, and sometimes even the exact cause of your concern.

Against popular belief, OBD2 scan tools aren’t just for scanning a Check Engine light. They can be used to diagnose scores of different issues, from ABS concerns and rough running problems to airbag systems and power accessory problems. If it’s connected to the vehicle network, there’s a good chance an OBD2 scan tool can help find the problem.

You’ll need to find an OBD2 scan adapter that not only works for your vehicle, but works for the symptom you’re tackling. Some scan tools only perform basic functions while others are capable of nearly the same functionality as the car dealership’s equipment. You’ll need to narrow down a few different criteria to find the right scan tool for your needs.

Select a Scan Tool for Your Vehicle

At the top of the list of requisites is vehicle information. Do you need a scan tool just for one particular vehicle or are you using it for multiple vehicles? If there’s a good chance that you’ll be working on multiple cars, or if your friends will pop by for you to clear their Check Engine lights, you’ll want to locate an OBD2 scan tool that is capable of many different brands.

To be clear, most scan tools can access very basic information on most models. But carefully review the manufacturer’s information for the specific models you know you’ll be working on.

While searching scan tool listings and reviews, you’re likely to find that some scan tools aren’t compatible with certain makes and models. For example, the Autel AL519 is an excellent all-around scan tool, yet it won’t work with early OBD2 GM vehicles in some cases. Other times, it might be premium brands such as Audi, BMW or Mercedes-Benz that are inaccessible.

Compile a list of several scanners across various price ranges that are known to work on your vehicle’s year, make, and model. This short list likely contains your new OBD2 scan tool.

Select a Scan Tool for Your Needs

If you’re searching for a scan tool, you probably have a specific concern you need to fix. It might be a Check Engine light on, an engine stumble, an ABS light or unwanted activation, or it could be a perplexing intermittent problem. Whatever your symptom, narrow it down to its broad system. Think about these categories:

  • Engine management
  • Drivetrain (including transmission)
  • Anti-lock Brakes (or traction control)
  • Airbag system
  • Body controls

This should help you narrow down if a scan tool is able to help you diagnose your concern.

If you drive a specialty brand, this is especially important. Where OBD2 scan tools can usually work at least on a limited basis for most cars, some German and Asian cars require specific equipment. As an indication, some BMW cars and SUVs require special connectors and software like the Autek INPA system.

Generally, the most common reason for purchasing a scan tool is to diagnose and clear a Check Engine light. If that’s your reason, the most cost-effective scan tool on your list is probably sufficient. However, if you know that your vehicle is susceptible to certain types of problems other than engine systems, you’ll want to look a little closer.

Drivetrain components become more commonly found on OBD2 scan tools in the lower end of the price range. If you need to diagnose an ABS or airbag problem, prepare to shell out a little more cash. Look much closer at the scan tool’s capabilities too. Often, while you’re trying to save a few bucks on a scan tool purchase, you’ll buy one that doesn’t perform to your expectations because you weren’t looking close enough.

If you have airbag, ABS, or body control issues that you’re trying to diagnose, one hint is to look for a scan tool that can decipher your VIN number. That usually indicates the ability to read manufacturer-specific codes like body codes. Without that ability, you might find the codes in the computer are incomplete or incorrect.

Choose an Easy-To-Use Scan Tool

Easy-to-use means different things to different people, so consider your level of ability when you read this section.

Basic Scanner/Code Reader

If you’re a newbie to vehicle diagnostics, you don’t want to read a 500-page manual before you can connect your scan tool to your car. A plug-and-play OBD2 scan tool is probably right for you. These ones are basic in their function and operation, mainly used for reading powertrain codes and clearing engine lights. On some, Freeze Frame data may be available so you can determine if a sensor is functioning as it should. It’s probably only two to four buttons on a tiny handheld tool. A common and great basic scan tool is the Autel AutoLink AL319. Beware the short cord, though.

Intermediate Scanner

If you’re a little more experienced and knowledgeable in vehicle repairs and diagnosis, you’ll want to step up to a higher-functioning model. An indicator is a somewhat larger screen with a few more buttons. It’s probably the size of a GameBoy with about 10 buttons on it. You’ll be able to navigate more quickly through screens. The operation will feel more intuitive if you have some technical knowledge. In most cases, you’re still looking only at powertrain codes. The Foxwell DIY NT301 scan tool is a good example

Wireless Scan Tool

If you’re looking for a slick tool that’s simple to operate, out of the way, and wireless, there are several Bluetooth and WiFi scan tools on the market now. You can use either your laptop or smartphone to connect to a scan tool that plugs into the OBD2 connector under your dash. In many cases, you can leave the connector plugged in indefinitely for easy connectivity, with no ill effect. It’s quite likely it will read and decode your VIN for you too.

With this option, you’ll have to download an app to connect to your scan tool. That’s not usually much of an issue, however you’ll need to pay close attention to the type of scan tool you buy. Nearly all Bluetooth scan tools connect to either an Android device of an Apple device, not both. If you buy the wrong one, you’ll have to send it back or find a buddy who needs one. One of the most popular and highest rated Bluetooth scan tools for iPhone and other iOS devices is the BlueDriver Bluetooth Professional OBDII scan tool. It’s incredibly versatile across most vehicle brands and has great support.

There are free apps you can use to control your Bluetooth scan tool’s basic functions, and other paid apps that do a much more thorough job. It’s worth the investment to get the higher-functioning app.

Tablet-Style Scan Tool

For the serious DIYer and even for some mechanic shops, the haute couture of scan tools is a tablet style. Usually they are either Windows-based or Android-based. Some have wired connections while others have Bluetooth or WiFi connectivity. These ones are going to be the best all-around scan tools, capable of communicating with virtually every OBD2-equipped vehicle, and virtually every system.

When you buy one of these high-end tablet-based scan tools, you’re going to get a kit with several different connectors for different vehicles and systems. If you’re going to be working on multiple vehicles, or if it’s going to be a professional-use tool, you’ll love it.

Scanners of this nature include the Autel Maxisys Elite. It decodes VIN numbers, operates on most every make or model, and includes diagnostic connectors in a hard plastic kit. While you’ll never use most of the connectors included, one or two will come in handy for sure. The Autel Maxisys Elite and kits in similar composition aren’t for the newbie or occasional user. These are hardcore, high-power systems meant for experienced operators. While it’s intuitive for technical minds, others will flounder to figure it out.


If you’re just looking to clear your Check Engine light, there’s no need to spend huge money on a scan tool. There are tons of good, basic scan tools on the market that will do just fine. If you’re looking for a backyard-mechanic or professional-grade scanner, however, what you pay reflects what you get in quality and functionality.