Unlock your car’s hidden diagnostics with the best OBD-II scanners. These essential tools connect to your vehicle’s computer, providing access to a wealth of information about its health and performance. Whether you’re facing a mysterious dashboard light or simply want to understand your car better, an OBD-II scanner empowers you to diagnose issues yourself, potentially saving money on professional mechanic fees.
Navigating the world of OBD-II scanners can be overwhelming, especially for beginners. With countless options available, it’s crucial to choose the right one for your needs. Having rigorously tested a variety of OBD-II scanners, we’ve compiled a list of top recommendations to guide you. Keep reading to discover our expert picks and a comprehensive guide to understanding OBD-II scanners, error codes, and how to select the best one.
Among our top selections, the Topdon TopScan stands out as an exceptionally user-friendly wireless option, packed with features for effective diagnostics. For budget-conscious users, the Launch CR529, priced around $40, delivers impressive functionality. If you require professional-grade diagnostics, the Topdon Phoenix Lite 2, though at a higher price point of $799, offers a comprehensive diagnostic experience comparable to professional tools.
Here are our recommended OBD-II scanners, categorized to help you find the best fit:
Tom Pritchard
Tom is the UK Phones Editor for Tom’s Guide, covering mobile technology and apps. He’s also a passionate advocate for electric vehicles.
Top OBD-II Scanners: Quick Recommendations
For those in a hurry, here’s a quick list of the best OBD-II scanners based on our hands-on testing. Scroll down for detailed reviews and insights into each product.
1. Topdon TopScan: Best Mobile OBD-II Scanner
The Topdon TopScan excels as a Bluetooth scanner, offering effortless setup and a suite of professional-grade features within a compact design. Expect comprehensive diagnostics, repair guidance, parts lists, and even predictive analysis to anticipate potential issues.
Explore the Topdon TopScan in Detail
2. Launch CR529: Best Budget-Friendly OBD-II Scanner
The Launch CR529 is a small yet powerful scanner delivering essential OBD-II functionalities along with advanced features typically found in higher-priced models. Lifetime support and updates add exceptional value to this affordable scanner.
Discover More About the Launch CR529
3. Topdon Phoenix Lite 2: Best Rugged OBD-II Scanner
Resembling a Nintendo Switch in its robust design, the Topdon Phoenix Lite 2 is built for both professionals and DIY enthusiasts. Its rugged construction and powerful capabilities make it ideal for those needing a durable and high-performance scanner.
Learn More About the Topdon Phoenix Lite 2
4. Ancel BD310: Best Dual-Purpose OBD-II Scanner
The Ancel BD310 serves as both an effective OBD-II scanner and a supplementary dashboard display for engine metrics. Its sleek design, smartphone compatibility, and reasonable price enhance its versatility.
Read More About the Ancel BD310
5. Carly OBD-II Scanner: Best OBD-II Scanner with Companion App
The Carly OBD-II Scanner’s utility is highly dependent on your car make, with optimal performance for VW, BMW, and Ford vehicles. It features an exceptional companion app offering extensive customization and professional-level diagnostics.
Explore the Carly OBD-II Scanner Further
In-Depth Reviews: Finding the Best OBD-II Scanner for You
Why Trust Tom’s Guide? Our team rigorously tests and reviews products to provide trustworthy recommendations. Learn about our testing methodology.
1. Best Mobile OBD-II Scanner: Topdon TopScan
(Image credit: Topdon)
Topdon TopScan
Ideal for comprehensive vehicle diagnostics and performance insights.
Read our full expert review
Key Specs:
- Display: None (App-based)
- Connectivity: Bluetooth
- I/M Readiness Test: Yes
- Live Data Display: Yes
- Keys: None (App-controlled)
- Warranty: 2 years
- Dimensions: 3.2 x 2.0 x 1.1 inches
- Weight: 2.6 ounces
Pros:
- Extensive vehicle diagnostic coverage
- Real-time live data monitoring
- Performance metrics and analysis
- Maintenance feature coverage
Cons:
- Bulky transmitter
- Subscription required for some features after one year
The Topdon TopScan might appear unassuming, but this compact scanner is surprisingly powerful. More than just a standard Bluetooth OBD-II adapter, it offers advanced capabilities exceeding many competitors in its class.
Beyond basic fault detection and I/M Readiness tests, the TopScan excels in performance and efficiency analysis. It can even estimate your car’s horsepower and torque, features rarely found in scanners at this price point, or even those costing ten times more. Whether you aim to optimize your vehicle’s performance or ensure its roadworthiness, the Topdon TopScan is a valuable tool to have.
Read our detailed Topdon TopScan review
2. Best Budget OBD-II Scanner: Launch CR529
(Image credit: Future)
Launch CR529
The best OBD-II scanner under $50, offering exceptional value.
Read our expert review
Key Specs:
- Display: 2.8-inch Color
- Connectivity: Handheld (No Bluetooth)
- I/M Readiness Test: Yes
- Live Data Display: Yes
- Keys: 8
- Warranty: 1 year
- Dimensions: 6.5 x 3.8 x 1.2 inches
- Weight: 11 ounces
Pros:
- Affordable price
- Lifetime free updates
- Easy pre-inspection reporting
Cons:
- Lacks manufacturer-specific codes
- Feels somewhat heavy
- Limited 1-year warranty
The Launch CR529 is arguably the best value OBD-II scanner on the market. Its low price of around $38 belies its impressive diagnostic capabilities. For such a budget-friendly scanner, the features are remarkably comprehensive.
While compromises exist, such as the absence of manufacturer-specific codes and a slightly heavy feel, the CR529 still provides live data, instant vehicle inspection reports, and detailed insights into your car’s systems. Lifetime updates ensure long-term usability without subscription fees.
Although the CR529 might not satisfy professional mechanics, it’s an excellent choice for most car owners seeking a reliable and affordable diagnostic tool.
Read our full Launch CR529 review
3. Best Professional-Grade OBD-II Scanner: Topdon Phoenix Lite 2
(Image credit: Future)
Topdon Phoenix Lite 2
Bridging the gap between amateur and professional vehicle diagnostics.
Read our expert review
Key Specs:
- Display: 8-inch Color Touchscreen
- Connectivity: Bluetooth, Wi-Fi, Handheld
- I/M Readiness Test: Yes
- Live Data Display: Yes
- Keys: Touchscreen
- Warranty: 2 years
- Dimensions: 10.2 x 7.2 x 1.7 inches
- Weight: 2.6 pounds
Pros:
- Professional-grade OBD scanner capabilities
- Wireless and handheld operation with Wi-Fi & Bluetooth
- Large 8-inch touchscreen
- Extensive diagnostic tests and live data features
- Includes adapters and protective hard case
Cons:
- Large, heavy, and can be cumbersome
- High price point
- Subscription required after two years for updates
The Topdon Phoenix Lite 2 is a significant investment, costing more than many other capable OBD-II scanners. However, it delivers exceptional value, offering features suitable for both amateur and professional mechanics.
Its wireless design, with a Bluetooth receiver connecting the control pad to the car’s OBD port, provides unparalleled freedom of movement. Despite its bulky and heavy build, the scanner features a kickstand and rugged construction, ensuring durability in workshop environments.
Advanced features like live data graphing, detailed fault information, and more, surpass the capabilities of cheaper scanners. Note that firmware updates are included for two years, after which a yearly subscription of $495 is required.
Read our full Topdon Phoenix 2 Lite review
4. Best Dual-Purpose OBD-II Scanner: Ancel BD310
(Image credit: Tom’s Guide)
Ancel BD310
A versatile OBD-II scanner that doubles as a car performance display.
Read our expert review
Key Specs:
- Display: 2-inch Color
- Connectivity: Bluetooth, Handheld
- I/M Readiness Test: Yes
- Live Data Display: Yes
- Keys: 4
- Warranty: 3 years
- Dimensions: 5.1 x 2.4 x 0.6 inches
- Weight: 5.4 ounces
Pros:
- Lightweight and compact design
- Functions as both a scanner and secondary car display
- Offers handheld and Bluetooth scanning options
Cons:
- Minimalist interface
- Small screen size
The Ancel BD310 is a dual-function scanner that operates as a standard handheld device and connects to smartphones via Bluetooth. Its unique capability to function as a secondary display showing key engine data within the car cabin adds to its appeal.
Its compact and lightweight design makes the BD310 highly portable, easily storable in a glovebox. The 2-inch screen is admittedly small, and the four-button interface can feel slightly awkward, but it remains functional for vehicle diagnostics.
The 56-inch cable is ideal for under-hood work, and the BD310 performs essential functions such as I/M readiness tests and displaying performance metrics, including coolant temperature, engine timing, and speed.
Read our full Ancel BD310 review
5. Best OBD-II Scanner with Companion App: Carly OBD-II Scanner
(Image credit: Carly)
Carly OBD-II Scanner
A dependable scanner whose value is car-dependent, enhanced by an excellent app.
Read our expert review
Key Specs:
- Display: None (App-based)
- Connectivity: Bluetooth
- I/M Readiness Test: No
- Live Data Display: Yes
- Keys: None (App-controlled)
- Warranty: Lifetime
- Dimensions: 2.9 x 1.5 x 0.7 inches
- Weight: 0.7 ounces
Pros:
- User-friendly app interface
- Customization options
- Real-time live data display
- Maintenance and repair features
- Lifetime warranty and updates
Cons:
- Feature availability varies by car model
- App subscription can be costly
The Carly OBD Scanner stands out for its exceptional companion app. While many Bluetooth scanners offer basic apps, Carly’s is among the best we’ve tested.
Beyond fault diagnosis and clearing codes, the app provides repair assistance and used car checks. A lifetime warranty adds further value.
However, feature availability is car-specific, with optimal functionality for VW, BMW, and Ford. Compatibility should be verified before purchase. Access to advanced features beyond basic OBD functions requires a subscription, which can add to the overall cost.
Read our full Carly OBD scanner review
Other OBD-II Scanners We’ve Tested:
- Innova CarScan Mobile 1000 (★★★★☆): An innovative Bluetooth OBD-II scanner with predictive diagnostics. Easy setup and wireless operation make it a strong Bluetooth option. Read the full Innova CarScan Mobile 1000 review
- ThinkCar ThinkDiag TKD01 (★★★★☆): A robust Bluetooth OBD-II scanner with extensive manufacturer-specific codes and error-fixing capabilities. Subscription required after the first year. Read our full ThinkCar ThinkDiag TKD01 review
- Autel AutoLink AL539 (★★★☆☆): Designed for electrical diagnostics with a built-in multimeter. Offers comprehensive live data and pre-inspection readiness checks. Read our full Autel AutoLink AL539 review
Frequently Asked Questions About OBD-II Scanners
What is an OBD-II Scanner?
Mechanics use diagnostic scanners plugged into a car’s OBD port to access the onboard computer and diagnose issues, rather than manual inspection.
Basic OBD-II scanners read and identify error codes flagged by the car’s computer when a problem is detected. Advanced scanners monitor car systems in real-time and may predict future issues.
What is the OBD-II Port?
The OBD-II (On-Board Diagnostics Version Two) port is standard on most passenger vehicles sold in the US since 1996, Canada since 1998, EU since 2004, and Australia, Mexico, and New Zealand since 2006.
This port connects devices like OBD-II scanners, insurance black boxes, and dash cams to the car’s computer.
Find your car’s OBD-II port location for North American vehicles, or worldwide OBD-II/EOBD port locations.
What is a DTC?
DTC stands for Diagnostic Trouble Code, an error code generated by a car’s OBD system when it detects a problem. OBD-II scanners read these codes to help users understand vehicle issues. Standardized DTC codes are common across vehicles, but some manufacturers use unique DTCs.
Understanding DTC Meanings:
DTCs may seem cryptic, but they follow a logical structure. The first letter indicates the affected system: Powertrain (P), Body (B), Chassis (C), or Network (N). The second character, a number, denotes whether the code is generic (0) or manufacturer-specific (1).
The third character specifies the subsystem:
- 1: Fuel and air metering
- 2: Injector circuit fuel and air metering
- 3: Ignition system or misfire
- 4: Auxiliary emissions
- 5: Vehicle speed and idle control
- 6: Computer auxiliary outputs
- 7, 8, 9: Transmission and gearbox faults
- A, B, C: Hybrid propulsion faults
The fourth and fifth characters define the specific fault (00-99).
OBD-II scanners interpret these codes, and advanced models provide detailed information. Online resources like Google can further clarify DTC meanings. There are over 5,000 possible DTCs, ranging from critical issues to minor warnings like slightly high engine temperature.
Choosing the Best OBD-II Scanner: Key Considerations
For understanding your vehicle’s health and diagnosing issues, OBD-II scanners are invaluable. They provide the same diagnostic capabilities used by professionals. When selecting an OBD-II scanner, consider these types and features:
Types of OBD-II Scanners:
- Handheld OBD-II scanners: Feature an integrated screen and cable.
- Wireless OBD-II scanners: Connect via Bluetooth to smartphones or tablets.
High-quality OBD-II scanners are available for under $200, with some even under $30. The best scanners balance size, features, and accuracy. Key criteria include:
- Easy Setup: Quick setup for immediate diagnostics.
- Faults and Explanations: Clear fault codes and understandable explanations.
- I/M Readiness Check: Emissions test readiness verification.
- Accuracy: Reliable and precise diagnostic results.
- Size and Weight: Portable and easy to handle.
- Live Data: Real-time engine parameter monitoring.
- Graphs: Visual data representation for trend analysis.
- Warranty: Long-term coverage and reliability.
Further Considerations:
- Connectivity: Choose between handheld or wireless based on preference.
- Longevity: Prioritize lifetime warranties or software updates.
- Screen Size (Handheld): Opt for a large, clear, and user-friendly display.
- Durability: Consider rugged models for demanding environments.
- Extra Features: Look for multimeters, manufacturer-specific codes, PDF export.
- Price: Professional-level features are available for under $100, offering excellent value.
How We Test OBD-II Scanners
Our OBD-II scanner testing involves weeks of use in real-world conditions. Using a 2014 Audi A4 Allroad, we evaluate each scanner’s performance in the garage and on the road. Testing steps include:
- VIN Verification: Confirming accurate vehicle identification.
- Connectivity Testing: Bluetooth/Wi-Fi range and stability for wireless scanners; cable length for handhelds.
- Live Data Monitoring: Engine and system data observation during vehicle operation.
- Fault Code Generation and Reading: Simulating and diagnosing issues by disconnecting sensors (e.g., oil temperature sensor).
- Code Clearing: Verifying the scanner’s ability to clear fault codes and check engine lights.
- Road Testing: Evaluating live data display (engine speed, timing, coolant temperature) in numerical and graphical formats.
We analyze the accuracy and detail of fault code descriptions. Fault codes consist of a letter prefix (Powertrain, Body, Chassis, Undefined) and four numbers. The numeric part starts with ‘0’ for generic codes and ‘1’ for manufacturer-specific codes.
For example, P0098 indicates a generic intake air temperature sensor issue. A Ford-specific code like P1112 for the same sensor indicates an intermittent issue requiring sensor replacement.
By rigorously testing OBD-II scanners, we aim to identify the best options based on practical performance and user needs.
