Communicating with your car’s Engine Control Unit (ECU) is crucial for identifying problems and maintaining your vehicle’s health. When the engine management light (EML) illuminates on your dashboard, the ECU holds the key to understanding why. Even without the EML, the ECU can log issues, track service needs, and monitor the performance of various components. Mobile OBD2 scanners offer a convenient way to access this vital information directly from your smartphone.
What is a Mobile OBD2 Scanner?
To tap into the wealth of data stored within your ECU, you need a scanner or fault code reader that connects to your car’s communication port. This port has been standardized as the OBDII (On-Board Diagnostics II) port. OBD2 ports have been a standard in vehicles for decades, becoming mandatory in the US around 1996, in European gasoline cars from 2001, and in diesel cars from 2004. Typically, you’ll find this port located beneath the driver’s side dashboard, although it can sometimes be in the center console area. Mobile OBD2 scanners take this diagnostic capability and put it in your pocket, utilizing Bluetooth technology to connect with your smartphone.
How We Tested the Best Mobile OBD2 Scanners
The mobile OBD2 scanners we tested are compact dongles that plug into your car’s OBD2 port and communicate wirelessly with your mobile phone or laptop via Bluetooth. These devices offer a cost-effective alternative to dedicated scanners with built-in screens, making car diagnostics accessible to a wider audience.
Our testing involved seven leading Bluetooth OBD2 scanners, all sharing a similar setup process. The first step is downloading a compatible app to your smartphone or laptop. Some scanners require their own dedicated apps, while others are compatible with a range of third-party applications, offering greater flexibility.
Next, you simply plug the Bluetooth OBD2 device into your car’s OBD2 port, turn on the ignition, and launch the app on your phone or laptop. We found the Bluetooth connection process to be consistently straightforward and quick across all devices tested.
With extensive experience in car diagnostics, we were particularly interested in evaluating the performance and capabilities of these budget-friendly mobile scanners. Continue reading to discover our in-depth findings.
Best Mobile OBD2 Scanners At A Glance:
vLinker MC+
Award: Best Overall & Best Value
Pros: Informative indicator lights for connection status, user-friendly setup.
Cons: Extensive third-party app compatibility can be overwhelming for beginners.
RRP: From $59.99 / £59.95
vGate, a well-known Chinese electronics manufacturer, offers a wide array of OBD2 scanners. The vLinker MC+ stands out for its ease of use, living up to its promise. The device features clear indicator lights on its front, displaying connection status and power supply, which greatly simplifies the pairing process. A dedicated connect button further aids in establishing a Bluetooth link with your chosen app. The vLinker MC+ offers broad compatibility, working with numerous third-party apps on Android and iOS smartphones, as well as Windows PCs and laptops.
The vLinker MC+’s versatility shines through its app compatibility. Depending on the app selected, users can access a wealth of in-depth vehicle information. In our testing, using the “Car Scanner” app, the vLinker MC+ accurately diagnosed a parking sensor issue on an Audi A3. It performed a comprehensive system check and provided live data monitoring of engine parameters, fuel consumption calculations, and even acceleration timing.
For a more detailed exploration of the vLinker MC+ scanner, refer to our full review.
OBDeleven
Award: Editor’s Choice
Pros: Straightforward fault code scanning, user-friendly interface.
Cons: Optimized for VAG, BMW, and limited other vehicle brands.
RRP: From $88.34 / £69.95
The OBDeleven, one of the most compact mobile OBD2 scanners in our test, presented some difficulty in disconnecting from the OBD2 socket in certain vehicles due to its small size. However, the included keyring attachment provides some leverage, and a universal extension cable is also available as a solution.
This scanner utilizes a dedicated app tailored for specific vehicle brands, primarily VAG (Volkswagen Audi Group), BMW, and Rolls-Royce. During our testing on different vehicles, the app sometimes automatically identified the car, while other times it required manual VIN entry.
The free, entry-level app offers basic yet effective functionality. It scans for fault codes and, in some cases, conducts detailed scans of systems like audio, parking sensors, and airbags. Identified faults are clearly presented with relevant fault codes and supplementary information.
Beyond fault code reading (and live data for supported brands), the free app’s features are limited. For advanced functionalities such as one-click apps to modify vehicle settings or perform system tests, users need to upgrade. This can be done through a Pro subscription (annual fee starting from $53.29) or by purchasing credits (from $2.19).
With a two-year warranty and a user-friendly free scanning app, the OBDeleven is a reliable and no-frills mobile OBD2 scanner, especially for owners of VAG and BMW vehicles.
For an in-depth analysis, check out Rob’s comprehensive review of the OBDeleven here.
TopDon TopScan
Award: Approved
Pros: Excellent dedicated software for fault diagnosis, robust functionality.
Cons: Incompatibility with 32-bit Android phones, subscription required after the first year for full app features.
RRP: $69.99 / £59.49
TopDon, a seasoned manufacturer of professional-grade car diagnostic tools, offers the TopScan mobile OBD2 scanner aimed at the DIY user. It requires downloading a dedicated app, but we encountered compatibility issues with 32-bit Android phones (64-bit required), a problem not seen with other scanners tested. For iPhones running iOS 10 or later, the “TopGuru” app is necessary, a detail not immediately apparent until we contacted their responsive support centers in both the US and China.
Once the correct app is installed, connecting to the TopDon scanner is quick and seamless. A diagnostic trouble code (DTC) scan successfully identified a parking sensor fault, a finding shared by only two other scanners in our test (OBDeleven and vLinker MC+). Automatic vehicle identification was unsuccessful in our case, necessitating manual vehicle selection starting with the manufacturer. We appreciated the inclusion of “Hot Functions,” such as oil service and battery reset. However, the absence of live data streaming, freeze-frame data, or a dashboard for real-time engine monitoring is a drawback. Furthermore, the full app functionality is only free for the first year, requiring a $49-$99 annual subscription thereafter.
For a deeper dive into the TopDon scanner’s capabilities, read Rob’s full review here.
OBDLink CX
Pros: Free dedicated app, compatible with third-party apps like BimmerCode, compact design.
Cons: Extremely small size makes it difficult to physically remove from the OBDII port.
RRP: From $79.99 / £78
The OBDLink CX is the entry-level mobile Bluetooth scanner from US-based OBDLink. Its ultra-compact design allows for discreet storage in a glovebox or center console. However, its small size made it challenging to grip and unplug from the OBDII port. Fortunately, UK supplier Gendan offers a 20cm extension cable to alleviate this issue.
A concise and user-friendly guide, including a QR code for downloading the free OBDLink app, is included. After installing the app on a smartphone, connecting is a simple process of starting the car, plugging in the device, and launching the app. While connection took a couple of attempts in our testing, it was generally quick. The app itself is straightforward with an intuitive menu.
The diagnostic function is responsive, but it unfortunately missed an existing parking sensor fault in our test vehicle.
We liked the dashboard feature, which provides real-time readings for engine RPM, speed, MAF pressure, battery voltage, and fuel level. This can be used in conjunction with freeze-frame data when a fault is logged. The app also includes trip logging, calculating fuel consumption and mileage, and the ability to display live data as graphs.
While OBDLink offers more feature-rich scanners at higher price points, the CX version serves as a capable and affordable entry into mobile car diagnostics.
Read the OBDLink CX full review for more details.
OBDLink MX+
Pros: Free app with advanced diagnostics, comprehensive feature set.
Cons: Marginally better than the significantly cheaper CX model, higher price point.
RRP: From $139.95 / £129.95
OBDLink’s premium mobile Bluetooth scanner, the MX+, packs a powerful punch with a wealth of free features. It’s also the most expensive scanner in our test group. The app, compatible with smartphones and even Kindle Fire devices, installs quickly. Connecting the scanner is equally fast and effortless – simply plug it into the OBDII port and open the app. A button on the scanner is included as a troubleshooting aid. A brief user guide simplifies the entire process.
The dedicated OBDLink app is exceptionally user-friendly, featuring a concise seven-option menu.
The depth of diagnostic analysis, especially using enhanced diagnostics, is impressive. The MX+ accurately identified a parking sensor fault that hadn’t triggered the EML.
Additional features abound, including versatile live data analysis. The Dashboard presents instrument-style readouts, while the Graph function visualizes data trends. The Map function enables trip data logging for parameter analysis and MPG calculation, and the Performance function calculates acceleration metrics.
The MX+ offers enhanced diagnostic capabilities that justify its higher price compared to the CX, particularly for users needing in-depth analysis. However, for basic diagnostics, the CX offers significant value at a lower cost.
Explore the OBDLink MX+ full review for a complete assessment.
UniCarScan UCSI-2100
Pros: Wide selection of dedicated and generic free apps, broad compatibility.
Cons: App choice can be overwhelming for users, parking sensor fault detection missed in testing.
RRP: From $79.99 / £54
Manufactured by WGSoft in Germany, the UniCarScan UCSI-2100 is a compact mobile Bluetooth OBD2 scanner compatible with a vast range of apps across smartphones (iOS and Android), and Windows PCs or laptops. These apps include dedicated options for brands like BMW and Opel, as well as generic apps like WGSoft’s own ScanMaster.
Connecting to a phone or laptop after plugging into the OBDII port is rapid. The level of detail available depends on the chosen app, but can be quite extensive. ScanMaster, for example, offers nine menu options, although some features require in-app purchases. Trouble codes are quickly retrieved, but in our tests, the UniCarScan failed to detect a parking sensor issue. Freeze-frame data is a valuable feature, capturing parameter values at the moment a fault occurs. Live data aids in analyzing engine performance for deeper diagnostics.
The UniCarScan UCSI-2100 is a practical and affordable mobile solution for emergency diagnostics and routine fault checks at service intervals, easily stored in a glovebox.
Read Rob’s comprehensive review of the UniCarScan scanner for more information.
vLinker FD+
Pros: Compatible with a wide range of third-party apps for Windows, Android, and iOS.
Cons: Extensive app compatibility requires users to experiment to find optimal software.
RRP: From $49.99 / £42
The vLinker FD+, another offering from vGate (China), is a globally available compact Bluetooth scanner. It features indicator lights for connection status once plugged in. Its small size, however, can make removal from the OBD2 socket slightly difficult.
Selecting a compatible third-party app for the vLinker FD+ can be challenging due to the sheer volume of options, including numerous dedicated apps. Pairing with smartphones or Windows laptops is straightforward and reliable. Depending on the chosen app, users can access detailed fault information and live data for in-depth analysis.
The vLinker FD+ provides a solid entry point into car diagnostics and live data retrieval at an affordable price.
Explore the vLinker FD+ full review for further details.
How to Buy the Best Mobile OBD2 Scanners
Choosing the Best Mobile Obd2 Scanner can seem daunting given the variety of options. There’s no single “best” answer; the ideal scanner depends on your specific needs. Start by considering your primary use case. If you mainly need to diagnose the EML when it illuminates, any of the scanners tested will suffice. However, some scanners offer enhanced diagnostics for specific car brands, which is beneficial if your vehicle is supported. For example, BMW owners might consider scanners compatible with the BimmerCode app.
Compatibility is crucial. Newer vehicles (from 2017 onwards) often use CAN-Bus (Controller Area Network) systems for ECU communication, a type of OBDII protocol supported by some scanners. If your car is newer, verify compatibility with the scanner manufacturer or supplier before purchasing. We found all manufacturers contacted to be very helpful in addressing compatibility queries.
All scanners tested can reset the EML by clearing fault codes. If you require additional reset functions, such as oil service light reset, some scanners offer this as a standard feature, while others may require a paid upgrade, pro package, or subscription.
Similarly, advanced features like live data, MPG calculation, and dashboard displays vary across models and may require additional costs. Consider whether these features are genuinely useful for your needs or simply added extras.
For more information on car diagnostics, explore further resources online and consult automotive repair professionals.
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