Best Budget OBD2 Car Diagnostic Scanner

Explore your options for the best and cheapest OBD2 scan tool

Mechanic looking at OBD2 Car Diagnostic Tool next to car engine in shop

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When it comes to automotive diagnostics, there's really no substitute to the kinds of diagnostic tools used by professional mechanics and technicians. But the technology has come a long way in recent years, and there are ways for determined do-it-yourselfers to save money with a car code reader.

Getting at the Codes

The simplest scan tools are OBD-II code readers. These are the kinds of devices you'll find at your local auto parts store. They are often affordable and can help point you in the right direction of a problem. But knowing the trouble code is only the first step in a potentially long and complicated diagnostic process.

Live Data Streaming

To be a really useful car diagnostic tool, a scanner should be able to interface with the car’s computer and display live data. Some scan tools are only designed to show a long list of all the available data values, while others allow you to pull specific parameter IDs (PIDs) and create custom lists. This can be tremendously useful during the diagnostic process because it allows you to watch for problems during a test drive.

You can find decent scanners that perform these functions for under a hundred dollars, although the cheapest option may be an ELM 327 scanner. These scanners plug into your OBD2 port and use an ELM 327 microcontroller to interface your car's computer with a phone, tablet, or laptop. You can use a USB cable or Bluetooth setup to establish the connection. With a laptop or mobile device, you can buy premium ELM 327 software and still end up spending a lot less than you would on a traditional scanner.

The Best Car Diagnostic Tools Include Diagnostic Procedures

The one thing that all affordable code readers and scan tools lack is the knowledge base that the best car diagnostic tools often come with. In addition to pulling codes and displaying data in a highly efficient manner, professional scanners provide technicians with diagnostic procedures to follow. In some cases, they may include instructions to test the working condition of specific parts. Many shops also have access to programs like Mitchell and Alldata, which provide invaluable diagnostic flow charts and testing procedures.

Professional diagnostic technicians also have a wealth of personal experience to draw on. No affordable car diagnostic tool can match that level of expertise, nor can it compete with the data-intensive instructions of a tool like a MODIS or software like Alldata.

Finally, you can find a variety of free and paid services online to use in conjunction with an affordable scan tool. The key thing to remember is that if you’re experiencing a problem with your car, somebody else has probably experienced it before and has probably posted about it somewhere on the internet.