ELM 327

4 Reviews


What is the ELM327?

If you own a vehicle that’s been manufactured in or after 1996, the chances are that it has an OBD-II (also known as OBD2) interface. The On-Board Diagnostics protocol standard 2 is the unified system by which all vehicle computer systems can be accessed by external diagnostic devices. It’s used for reading out fault codes, identifying issues, clearing codes once the defects have been rectified, modifying certain aspects of the vehicle (known as coding), and service reminders. The beauty of the OBD-II protocol is that irrespective of manufacturer, any car is bound to have it — in fact, all gasoline (known as petrol in some countries) vehicles manufactured in Europe since 2001 are bound by law to be equipped with an OBD-II port, while all diesel vehicles manufactured since 2004 have to come equipped with this port.

There are many consumer-grade devices out there that act as an interface between the vehicle and the chosen OBD-II reader. The ELM327 is one of those devices. Produced by ELM Electronics, it’s a tiny microcontroller that acts as a bridge between the vehicle’s OBD-II interface and your chosen readout device. The readout device can be a desktop or laptop computer, tablet, or mobile phone. The versatility of the ELM327 means that it can connect with your chosen device via a wired USB connection or wirelessly through a WiFi or Bluetooth connection. Thanks to the ELM 327, novice and enthusiast vehicle users no longer need to invest heavily in professional-grade OBD-II readers and adapters that can cost thousands of dollars.

In fact, the ELM 327 is the most popular device from ELM Electronics’ suite of OBD-II microcontrollers, as it can read a broad gamut of OBD-II data across different vehicle manufacturers.

How do you use the ELM327?

Firstly, you must purchase an ELM327 adapter, ideally from an established vendor. Given how popular the ELM327 is, there are fakes on the market. These counterfeit products can provide erroneous data or damage your vehicle’s computer systems. Have a look at this link from OBD Advisor on their best genuine ELM327 adapters in 2022: https://www.obdadvisor.com/elm327/

When purchasing an ELM327 adapter, you can pick from wired or wireless connections. Wired connections are great for use with a desktop PC or laptop but are less versatile on the road. Wireless connections such as Bluetooth and WiFi mean that the ELM327 adapter can directly connect to your smartphone or tablet for diagnosis on the go. Bear in mind that Bluetooth offers a significantly lower data transfer rate than WiFi, and neither can match the data transfer rate of a wired connection, so if speed is king above everything else, wired is the way to go.

If you’re going down the wireless route, you also need to install a compatible mobile app on your smartphone or tablet. There are a variety of apps out there, including CarScanner, Torque Pro, and OBD Auto Doctor. Check out this link for five of the best: https://scanneranswers.com/best-elm327-software-free-download-windows-android-iphone/

Once you have purchased your ELM327 adapter and installed the app on your phone, you need to find the OBD-II port on your vehicle. This is inside the car and usually within a few feet from the steering wheel. Common places include underneath the steering wheel, inside the glove box aperture, or the center console box. Consult your vehicle’s user manual or do a quick Google search for your vehicle’s specific make and model if unsure. Plug the ELM327 adapter into the OBD-II port, and it should power on. If it doesn’t, check the instructions specific to your ELM327 adapter, as some may require an external USB power supply which can be obtained from your car’s mobile phone charging ports, or alternatively, you may use a USB power bank.

The next step is to pair your ELM327 device with your chosen app, and once again, instructions are dependent on the app and chosen ELM327 adapter. Typically, the app will ask you to connect the adapter to your car and switch on the wireless technology utilized by the device – Bluetooth or WiFi. In most cases, it’s as simple as pairing a headset!

How much does it cost?

Using an ELM327 adapter is very cost-effective. As per our previously provided link from OBD Advisor, you can pick up a device for as little as $15, with the most expensive device running you $65. Of course, this does not include the price of your chosen app, but most apps offer a limited free version that should suffice for most novice or occasional enthusiast users. Either way, you can easily get yourself a complete ELM327 solution consisting of an adapter and accompanying app for under $100, which is a great deal.

Considering that ELM327 is powerfully versatile, and many of the adapters are compatible with multiple apps across Apple and Android devices, it’s truly a cost saver. An OBD scan service at an established workshop can easily cost you $50 or more, and it’s recommended that you perform such scans at least once every two to three months, depending on how often you use your vehicle. This means that you can quickly recover the cost of your ELM327 investment with just two scans!

An additional cost benefit is that using an ELM327 device to read out your vehicle’s error memory means that you can easily identify and correct minor errors by yourself. Although modern cars are increasingly complex, there are still tasks that can be undertaken by enthusiast owners and users, such as changing batteries, oils, filters, and sensors. Undertaking these repairs at a workshop can easily result in three- or even four-figure bills when the cost of labor is taken into account, as well as the cost of alternative transport while your vehicle is in the workshop. 

Of course, you shouldn’t attempt any vehicle repairs unless you are fully competent at it, or else you may still need to visit a workshop in the end. But even if you’re not comfortable performing vehicle repairs, an ELM327 OBD-II scanner will allow you to identify potential issues at an early stage before they develop into major problems and compound.

Therefore, the cost (or rather, cost savings) of an ELM327 device goes beyond the outright purchase price of the device and accompanying app or software.

Where can I buy an ELM327 device?

You can buy them in a variety of places. Firstly, identify which device suits your need, and make a shortlist. You don’t want to just go online and purchase a fake, after all. Once you have made your shortlist, it’s prudent to visit the manufacturer’s website and either directly purchase from there or find a physical store and make a purchase. While third-party sites may be an appealing prospect in terms of discounts, we’d advise you to steer clear unless it’s a third-party site that’s expressly stated as a purchase point by the manufacturer. The reason for this is, it’s all too easy for random sites to sell fakes and lookalikes.

Purchasing from the manufacturer’s own website, recommended third-party site, or a physical store also means that you can get the benefits of any warranties provided, should the device become faulty during the warranty period. While it’s a small financial cost, it’s always nice to have that cushion of safety and peace of mind. 

Keep an eye out for special offers and bundle offers, as auto shops may run promotions or bundle offers on these devices. This tends to happen with older variants of the ELM327, as ELM Electronics periodically releases newer versions of the microcontroller. Older versions still have decent functionality and will work with basically any modern OBD-II equipped vehicle, so you might just snag yourself a bargain!

ELM327 Reviews

What are users saying about ELM327-based devices? We decided to do a little trawling on the internet to find out.

On Amazon, these devices tend to have four- or five-star reviews unless they are clones or cheap knockoffs. This may not be revealed by the seller, so ensure that it’s from an established manufacturer, or that the ELM version numbers match up at the very least. ELM Electronics’ website has a list of ELM327 versions produced. For example, one user review on Amazon stated that his device was claimed to run ELM 1.5, but there’s no official version of ELM marked as 1.5; so he was able to identify it as a clone.

OBD Advisor (https://www.obdadvisor.com/elm327-mini-review/) tested a genuine ELM327 Mini Bluetooth adapter in October 2021 and compared it to two alternatives. Customer reviews for this device were an average of four stars out of five. They applauded its broad range of functions, wallet-friendly price, and wide app support, but pointed out that it didn’t support hybrid vehicles, and leaving it permanently plugged into the OBD-II port could potentially drain your vehicle’s battery as it draws power from the OBD-II port to function. 

We found that most low (two or three out of five) reviews were because users were unwittingly pushed into purchasing clones or knockoffs that performed poorly. This illustrates the importance of ensuring that you are buying a legit ELM327 device to avoid getting scammed and receiving a poor user experience. Users cited slow and buggy connections, patchy integration with software, and non-functionality with mainstream OBD-II mobile apps as some of the reasons for their poor reviews and subsequent discovery that the device was not a genuine ELM327 but a clone or knockoff.


OBD Devices


ELM 327




Torque Pro






Latest Reviews

Rated 1 out of 5
July 19, 2022

Worked for 20 minutes and quit

Rated 0 out of 5
July 19, 2022

Although this device worked for my wife’s Dodge RAM (1998), it failed to work on my Ford Escort (1996). Yes, both are OBD2.

Rated 4 out of 5
July 19, 2022

Super easy to use, just plug it into the OBD-II connector and connect with blue tooth. I use the Torquefree app on my Droid to pull and clear codes. you can pull a lot of basic functions, rpm, MPG, water temp, air temp, O2 sensors, etc… Works great for basic monitoring/road test and codes. I haven’t tried to use it for anything more as I have enhanced packages with my laptop and AutoEnginuity software.

Rated 5 out of 5
July 19, 2022

Plugged this into my 2010 Traverse and got all the read-outs on my tablet. Also cleared a check engine fault of a loose gas cap which has not come back since. Nice little unit.



Congratulations to Carly OBD

The Unrivaled Champion of Our OBD Device Showdown!

Breaking through the competition with stellar performance, unmatched diagnostics, and exceptional user experience, Carly OBD is our ‘Best OBD Device of 2023′! 

Excellence you can trust, the power of diagnostics in your hand – that’s Carly OBD.

Experience the Carly Difference today – the ultimate partner for your vehicle’s health and performance!

Congratulations to Carly OBD

The Unrivaled Champion of Our OBD Device Showdown!

Breaking through the competition with stellar performance, unmatched diagnostics, and exceptional user experience, Carly OBD is our ‘Best OBD Device of 2023′! 

Excellence you can trust, the power of diagnostics in your hand – that’s Carly OBD.

Experience the Carly Difference today – the ultimate partner for your vehicle’s health and performance!