There are hundreds of consumer-grade OBD2 scanning solutions out there that use a wireless OBD2 scanner dongle paired with an app on a smartphone or tab to offer users the chance to conduct diagnoses on their vehicle wherever they are, perform in-depth analyses, monitor certain parameters in real time, engage in a spot of vehicle customization known as coding, perform maintenance tasks and so much more.

So how do you choose which one is best for you? We’ve simplified the task by taking three solid options called FIXD, Carly, and Carista. We are going to evaluate each one for its pros and cons, and present them to you to make your decision. After reading our article, you’ll be armed with everything you need to know about FIXD, Carly, and Carista, enabling you to make an informed choice.

Firstly, let us take you through what a consumer grade OBD2 scanner is, how OBD2 came about, and what you can do with it. Once we’ve laid the foundations, we’ll dive right in.

What Is a consumer-grade OBD2 scanner?

Every vehicle from a mainstream auto manufacturer that’s been sold since 2004 comes with a little-known port in the cabin known as the OBD2 port. This port is the portal that grants access to the vehicle’s myriad of computer systems, and is a critical interface for workshops and repair centers to diagnose issues with your vehicle, as well as perform a myriad of other important functions. You may have observed a technician plugging something beneath your vehicle’s dash when performing repairs or routine servicing. They are connecting an OBD2 scanner, typically a professional-level one that costs thousands of dollars and comes with highly advanced functions.

If it all sounds a bit daunting, don’t be put off. There are plenty of consumer-grade OBD2 scanners out there that allow the average layperson, keen auto enthusiast or DIYer to access much of the same information and functionality that workshops do. These devices can be found at varying price points, from $20 all the way to $500 and beyond. Some come as stand-alone wired devices, others require a cable to connect to a laptop with special software, and the most popular kind which we are focusing on today use a small and unobtrusive scanner dongle. This dongle plugs into your vehicle’s OBD2 port and stays mostly out of sight, as it communicates with a companion app on your smartphone or tablet via Bluetooth or WiFi. So, how did this wonder interface OBD2 come about?

What Is OBD2?

In the Eighties, vehicular emissions were a worldwide problem. California decided to do something about choking smog in the city and enacted a series of Clean Air acts, which mandated that vehicle emissions had to conform to set levels. More importantly, vehicles had to have an on-board system to continually monitor emissions, and alert the driver to any anomalies via the Check Engine Light (CEL). This was called OBD, or On Board Diagnostics. Manufacturers soon realized the versatility of OBD and started using it for diagnostics across the entire vehicle, not just the emissions control equipment.

However, the haphazard nature of OBD meant that manufacturers quickly developed their own interpretations and proprietary ports. Unifying all this was accomplished in 1996 by the introduction of OBD2, which unified the port and provided standard protocols, as well as manufacturer specific protocols. This allowed manufacturers to incorporate a degree of customization as they wished, while retaining wider compatibility across the standard functions that included emissions control equipment monitoring. Mandating a standard port meant that there no longer was a need for several adaptors and scanners, which was a boon to multi-brand workshops as they previously had to heavily invest in equipment for each brand that they handled. Now, they could purchase one universal device. As professional-grade OBD equipment can cost thousands of dollars, the cost savings were tremendous.

What Can I Do With OBD2?

What can you, as an average car user do with a consumer-grade OBD2 scanner solution? Quite a bit, as it turns out, that will save you workshop visits and associated costs. Here are some of the most popular things that an OBD2 scanner will grant you access to. Note that not all scanners have the same feature set, as we will see further in this article.

• Perform diagnostics of critical systems in your car such as emissions control equipment and engine control systems.
• Perform diagnostics on transmission, braking and steering systems.
• Check the functionality of safety systems such as airbags.
• Query all other systems for errors, such as climate control, infotainment, and body control module.
• Engage in customization, or coding where you can adjust parameters for several aspects of your vehicle, such as light flashing times, light illumination durations, engine start/stop functionality, climate control and infotainment systems.
• View a report of maintenance required on your vehicle.
• Perform maintenance counter resets and re-initialization after conducting maintenance tasks.
• Verify mileage on used cars to detect mileage tampering.
• Monitor certain parameters in real time while driving.
• Monitor the vehicle’s movements in real time, including acceleration, braking, speed, and GPS position, which is utilized by fleet operators such as car rental agencies and delivery companies.

Quick Comparison — FIXD, Carly and Carista

For those who are in a hurry, here’s our in-a-nutshell comparison of FIXD, Carly and Carista. We’d strongly recommend you read through the entire article for a more thorough explanation, but if you’re looking for a summary, here you go. Just don’t forget to read the rest of the article later on. The mobile app component for all three supports iOS and Android, and can be downloaded from the Apple App Store or Google Play Store.

Parameter	FIXD	Carly	Carista
Customer Rating	4/5 (Amazon)	4/5 (Amazon)	4.4/5
Cost	$39.99 (Amazon, discounted from $54.99)	$80.89 (Carly website, discounted from $120)	$49.99 per year (app) $29.99 (adapter)
Dimensions (LxWxH)	1.5 x 0.5 x 1.8	4.6 x 3.5 x 1.5	2.8 x 2.8 x 1.6
Weight of Dongle (ounces)	0.96	3.20	1.77
Basic OBD2 functions	Emission system check Read and clear fault codes Freeze frame	Emission system check Read and clear fault codes OE-level diagnostics	Emission system check Read and clear fault codes OE-level diagnostics
Advanced functions	Over 6	Over 5	Over 5
Coding	No	Yes	Yes
System Diagnostics	TPMS, ABS, Airbag, Transmission	All systems	All systems

What Is FIXD?

FIXD comprises a Bluetooth-enabled OBD2 scanner dongle, and the FIXD app that is compatible with iOS and Android smartphones and tabs, and the app may be downloaded from the Apple App Store or Google Play Store depending on your device’s operating system. Data is transmitted via the dongle to the app, and allows FIXD to offer a variety of functions, including:

• Real-time monitoring of engine performance parameters and identification of anomalies or malfunctions.
• Real-time display of Check Engine Light (CEL) indications and faults causing these.
• Monitoring of the transmission control unit’s parameters and functionality for anomalies.
• Checking and monitoring of safety systems such as ABS and Airbag control units.
• Monitoring of TPMS systems and detection of faults in these.
• Freeze frame function to read crucial alerts or unusual data values.
• Automated reminders for maintenance activities such as oil changes.
• Storage and retrieval of readings for later analysis.
• Analysis of error readings with some explanation.
• Suggested corrective measures that could be taken for detected errors.
• Free lifetime updates on the app.

Advantages of FIXD

• FIXD offers swift scanning and generation of reports, typically taking around one minute for an average scan. Other tools can take several minutes.
• You receive the report to your smartphone app, where you can view it, and share it via e-mail, instant messaging, or social media. This is useful for sharing it with service center personnel and technicians for further analysis and action.
• Automated maintenance minders are helpful to remind you when scheduled maintenance is due on your vehicle as per its recommended maintenance intervals. This helps avoid costly repairs due to situations such as running an engine for too long without changing the oil.
• FIXD can be configured to monitor up to five vehicles (you will need one scanner dongle per vehicle) on a single smartphone or tab, which is useful for families with several vehicles, or fleet operators.
• You can call the FIXD hotline six days a week and consult a mechanic for technical support.
• FIXD can show you real-time data for your vehicle, as well as each vehicle it is monitoring. Note that each vehicle must have its own scanner dongle installed for this to work.

Disadvantages of FIXD

• FIXD does not offer resetting of maintenance counters on the vehicle, or advanced maintenance functions such as re-initializations or DPF regenerations.
• Some users have reported that FIXD can produce erroneous alerts such as false O2 sensor alerts on initial use.
• The user interface is reportedly not as friendly as other offerings.
• FIXD can handle vehicles only if they do not exceed 14,500 GVW (Gross Vehicle Weight).
• The scanning capabilities of FIXD cover only a few systems.
• FIXD does not offer any coding / customization functions.

What Is Carly?

Developed in Germany, Carly initially focused on European cars, but has since grown to encompass American and Japanese models as well. Carly consists of the Carly Universal OBD Scanner which is the OBD2 scanner component, and the Carly app. There is also a Carly lite app with a limited gamut of functions available for free so that users may try out Carly before investing in the full version. Both versions of the app are available on the Apple App Store and Google Play Store. Carly offers a powerful feature set, including:

• OE-level diagnostics
• Easy to use and understand user interface aimed at a broad base of users.
• Coding / customization functions for some makes and models of cars.
• Broad support of almost every car with an OBD2 interface.
• Carly User Car Check for checking used cars for mileage tampering.
• Expert tech support and knowledge database.
• Comprehensive set of maintenance tools.
• Free lifetime updates on the app.

Advantages of Carly

• Carly uses a simple traffic light color coding system when performing diagnostic scans, categorizing each error under red, amber, or green. Red errors are critical and need immediate attention. Amber errors are important, but the vehicle may be driven for a while. Green errors are insignificant and may be disregarded.
• User friendly interface allows novices to quickly get to grips with the system.
• Carly’s full diagnostics suite offers OE-level diagnostics, and rivals some entry-level professional OBD2 scanner solutions.
• Real-time monitoring of some parameters is available.
• Comprehensive suite of maintenance tools that include resetting of maintenance intervals, re-initialization of new batteries and fault memories, and more, making Carly ideal for the DIY enthusiast.
• Decent gamut of coding / customization functions that allow you to adjust various aspects on certain vehicles. Depending on vehicle make and model, features that may be adjusted include behavior of turn signals on tap of indicator stalk, disabling engine start-stop system, setting climate control to default on recirculate, duration of ‘follow me home headlamps’, anti-theft alarm behavior and more.
• Coding backup feature allows you to roll back coding changes.
• Carly Used Car Check is a unique feature that allows detection of mileage tampering on used cars, by conducting comprehensive scans across multiple control units and analyzing for discrepancies.
• Carly can store data for later retrieval and analysis.
• Carly can read the DTCs from up to 80 vehicle modules, covering the latest vehicles and cutting-edge technology.
• Within the simplistic and user friendly interface lies a powerful set of features for advanced users as well.

Disadvantages of Carly

• Carly can be pricey for novice users or those who do not need such a large feature set.
• Currently, the coding function is mostly beneficial to those with European vehicles such as those manufactured by Audi, BMW, Mercedes-Benz, Volvo, Volkswagen, Mini, Skoda and Seat.
• Coding functions are still basic compared to professional level OBD2 scanners and dedicated coders.
• Carly’s advanced feature set can be hard to understand for those with little to no technical knowledge of modern vehicles.

What Is Carista

Carista is another solution that offers dealer-level diagnostics, coding and maintenance tools. Initially, Carista was only a software solution, and users could pair a hardware OBD2 scanner dongle of their choice with it. However, the best solutions are those that have been engineered for the hardware and software to work together, and Carista now offers its own OBD2 scanner. Working in conjunction with the Carista app that can be downloaded from the Apple App Store or Google Play Store, Carista offers the following features.

• OE-level diagnostics.
• An intuitive user interface.
• Advanced coding functions.
• Broad support of almost every car with an OBD2 interface.
• Live data function in real time.
• Can perform many of the same functions as the other two.
• Free lifetime updates on the app.

Advantages of Carista

• Can perform a comprehensive range of OE-level diagnostic scans and present results in an easy to understand manner.
• Coding functions are broader and more powerful than Carly, allowing you to code more features on a wider array of vehicles, and not just European vehicles.
• One click action for service resets simplifies maintenance reset activities, and the maintenance function range is as broad as Carly.
• Cheapest option of all three in this comparison.
• Carista can tell you how many times the airbags have been deployed on a vehicle, which is useful when checking out a used vehicle to determine if it has been in a severe accident.

Disadvantages of Carista

• There are extra fees to be paid for certain functions that are free on FIXD and Carly.
• There does not appear to be a way to roll back coding activities, unlike Carly.
• User interface can be a bit confusing when venturing deeper into function sets.

Which One Is Best For Me?

Which one is best for you? That’s a question that you should be able to answer after reading this article. We can’t answer it for you, as we don’t know your exact vehicle make and model, your level of expertise and interest in vehicles, why you’re buying a consumer-grade OBD2 scanner, or your usage scenario. All these characteristics are important when making an informed decision.

If price is your main concern, FIXD is the cheapest, and it’s also the best for novice users who just want a way to check their vehicle’s diagnostic status every now and then, so that they can take it in to the workshop and have it attended to.

If you’re more of a DIY enthusiast who enjoys a bit of coding, does some of your own maintenance on your vehicle, and in general prefer a more in-depth diagnostic scanning solution, Carly, and Carista both offer great feature sets at a similar price (if Carly is on discount). Choosing between the two is really down to the details, such as your vehicle make and model (Carly supports mainly European vehicles for coding and advanced functions), how much coding you want to do, and whether extras like the Carly Used Car Check are of use to you.

If you are in the habit of buying and selling cars because it’s your business, or you just like experiencing as many cars as possible, Carly’s Used Car Check can help you detect mileage tampering through its powerful analysis across control units, and is a feature well worth it. Carista’s airbag deployment detection is also great for identifying cars that have been in a severe accident and subsequently repaired.

In summary, each solution offers pros and cons, and we hope that this article will help you decide, and rest easy over it.