- 1 Best OBD2 Scanner Reviews – Top-Picks
- 2 What is an OBD-II Scanner?
- 3 Types of OBD2 Scanners
- 4 OBD1 Scanners Vs. OBD2 Scanners
- 5 How do OBDII Scanners Work?
- 6 What can an OBD-II Scanner Do
- 7 Issues an OBD-II Scanner Can Detect
- 8 6 Benefits of Owning a Code Scanner
- 9 How To Use A Diagnostic Code Scanner In 3 Steps
- 10 How to Read and Understand OBD Codes
- 11 FAQs and Answers
- 12 Best Obd2 Scanner Comparison Chart
- 13 Conclusion
Apart from turning off that ‘check engine’ light, the best OBD2 scanners can help you sidestep costly trips to the mechanic. These devices let you plug them into a port under your car’s dashboard and justify their asking price by pinpointing what is wrong with your vehicle.
Once you have that information at your disposal, you can spend your time and effort troubleshooting the exact issue. You won’t have to bury your head under your car’s hood or drive your vehicle to the mechanic to pinpoint what the problem might be.
Firefighting isn’t the only unique selling point of these scanners. They generate reports relating to your vehicle’s brake system, fuel system, transmission, and even emissions. Also, the fact that they have broad compatibility means you can use the same scanner with every car in your household.
Still curious about their offerings? Then check out our obd2 scanner reviews.
BlueDriver LSB2 Bluetooth Pro OBDII Scan Tool
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INNOVA 3160 Diagnostic Scan Tool
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FOXWELL NT301 OBD2 Scanner
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Autel AutoLink AL319 OBD2 Scanner
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ANCEL AD310 Universal OBD II Scanner
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NEXPEAK OBD2 Scanner
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Best OBD2 Scanner Reviews – Top-Picks
1. BlueDriver LSB2 Bluetooth Pro OBDII Scan Tool
The BlueDriver LSB2 Scan Tool is one of those models which offer a brilliant amalgam of high-end features and a competitive asking price. It is certified by the Association of Safety Engineer’s certified mechanics and generates unlimited vehicle specific reports for at least 13 different car manufacturers.
Regardless of the issue you might be facing with your car, this tool’s database of over 30 million fixes will present you with a solution. Its app is another one of the unique selling points of this product as it makes problem diagnosis and troubleshooting a cinch.
Another highlight of this OBDII scanner is its smog check option. You can take advantage of this feature to see if your car is ready for a smog check. You can customize its user-interface, rewind and freeze frame codes and also program this device to receive periodic maintenance and service reminders.
2. INNOVA 3160 Diagnostic Scan Tool
Here is another diagnostic scanner that works with all vehicles manufactured in or after 1996. It is compatible with both foreign and domestic cars. You can also count on this model to display and resolve error codes of light trucks, minivans, and even SUVs.
Its backlit screen provides live data in graphical, tabular and digital form. You have the option to freeze and rewind PCM data streams on its screen. Also on offer is the feature using which you can turn off check engine, ABS and SRS lights. It also lets you update its software by connecting with a Windows PC.
This diagnostic tool scanner has a built-in memory using which you can carry out your car’s analysis even without turning on your vehicle. You can dig deep into its menu to change its language from English to French and Spanish. Also, apart from generating error codes, it provides their definitions as well.
3. FOXWELL NT301 OBD2 Scanner
There are many features of this scanner which make it a good value for your money. It enables you to read and decipher diagnostic trouble codes, locate the source of bad O2 sensors, and tells you whether the emissions status of your vehicle is ready to meet emissions test or not.
Aside from that, this model turns off check engine light, resets your dashboard’s monitor, and delivers data in real-time. It gives you the option to retrieve the vehicle identification number of your vehicle and lets you view the entire data in graphical form to pinpoint any suspicious trend.
Yet another noteworthy feature of this scanner is its smog check helper. It consists of three lights (red, yellow, and green) to indicate the readiness of your automobile for a smog test. Also on offer is a built-in speaker whose automated voice would let you know whether or not your car is ready for a test.
4. Autel AutoLink AL319 OBD2 Scanner
Those of you who are on a budget will appreciate the offerings of this OBD2 scanner. It offers plug-and-play installation and comes with a user-intuitive interface. You won’t have to be an expert in vehicle diagnostics to navigate through this unit’s menu and identify what is wrong with your vehicle.
It was surprising for us to note that no corners have been cut to keep this model’s asking price low. It offers all those features which you usually get in scanners costing twice as much. They include live data relay, freeze frame, I/M readiness, check engine light diagnostics, and more.
Also on offer is a one-click I/M readiness key and a TFT color display. Its built-in speaker, as well as LED indicator, will let you know about the readiness of your car for a vehicle emissions test. The entire menu is available in seven languages, and the unit is warranted for a whole year.
5. ANCEL AD310 Universal OBD II Scanner
Provided you have no prior experience of using an OBDII scanner, you’d appreciate the user-friendly interface of the Ancel AD310 tool. This auto code reader contains only four buttons – two of which are for scrolling through its menus, whereas the other two are for entering and exiting.
Although it doesn’t offer advanced features like SRS, transmission and airbag systems check, this unit does let you carry out a smog check. It comes with a three-year warranty and supports multiple languages to remain useful for people of different educational backgrounds.
In addition to showing error codes, this device also shows their definitions. That saves you the time that you’d otherwise have to spend on consulting the internet to decipher those codes. Also on offer is a built-in memory, freeze frame data feature and an insulated 2.5 feet long cable.
6. NEXPEAK OBD2 Scanner
The Nexpeak OBD2 scanner is another one of those models whose asking price won’t blow a hole in your pocket. It is a professional-quality scanner that allows you to check and troubleshoot multiple engine related fault codes. It also gives the option to turn off check engine light and locate bad O2 sensors.
One feature of this model that impressed us the most was the one that lets you monitor the health of your car’s battery. It is a pretty handy feature to have as it tells you in advance when your battery needs replacement. That means you won’t wake up one day to find out that your battery has gone dead.
Despite being an economically-priced model, this scanner lets you read and resolve both manufacturer- as well as generic codes. It also gives you the option to automatically acquire your vehicle’s VIN and check out the status of its EVAP system. Definitions accompany all the codes that it generates.
What is an OBD-II Scanner?
Onboard diagnostics II scanner is a standardized tool that connects with the onboard computers in cars and trucks to self-diagnose and report malfunctions in different parts of the vehicle. It is connected to your vehicle via the OBD port that lays underneath the dashboard on the driver’s side.
Unlike earlier, OBD-I scanner, OBD-II systems have universal communication protocols, connectors and code designations. That is the reason why a single OBD-II scanner is capable of diagnosing and reporting errors of all vehicles made in or since 1996.
The functionality of OBD-II scanners is determined by whether you have invested in a basic ‘code reader’ or a high-end ‘scanner.’ Code readers only read and clear codes, whereas the high-end scanners offer real-time information, record and store data, and other advanced features.
OBD2 Scanner Buying Guide
Most people who go shopping for an OBD2 scanner make one fatal error. They don’t realize that just because a scanner is compatible with their car, comes in a glitzy packaging and claims to offer features they haven’t heard about before doesn’t mean it is the best for their vehicle.
Instead, as you’ll see in this section, these devices come with two types of features: those that you need and those that you don’t. You should only go for models whose features you’re more likely to take advantage of going forward.
5 Considerations When Buying an OBD2 Scanner
Ask yourself these questions before you go searching for an OBD2 scanner:
Do I want a basic code reader or a high-end unit?
If you don’t want to spend over the odds, a basic code reader might suit you better. These are low-cost devices that merely display error codes. You then have to decipher the codes to identify the problem with your vehicle. One downside with code readers is that they don’t work with the latest car models.
Conversely, if you’re a professional who wants to use their scanner across a wide range of vehicles, a high-end code scanner will serve you better. It offers various advanced functions like ABS capability, live data transmission, data storage or logging features, on-screen definition of error codes, and more.
Yet another benefit of top-rated OBD2 scanners is that they display the vehicle identification number (VIN) of the car. This information is crucial if you’re looking to buy a second-hand car – as entering the VIN into the government’s database will let you know whether the car is rebuilt or tampered with.
Tip: If the scanner reveals that your brakes have suffered excessive abuse, check out our brake controller reviews to find a product that will reduce the wear and tear of your vehicle’s brakes.
Do you plan to upgrade your car in the future?
As you might guess, inexpensive OBD2 scanners aren’t upgradable. All their built-in features serve cars that are already on the road. That’s why you might want to invest in a high-end OBD2 scanner if you are planning to get the latest model in the future.
Similar to how your smartphone operates, the high-end scanners receive periodic updates from their manufacturer. However, unlike your gadgets, the updates that these scanners receive aren’t free. Each of them comes with a price, so it’s recommended to inquire beforehand how much the updates might cost.
What signal protocol does your OBD2 scanner uses?
Knowing about the signal protocol that your OBD2 scanner might be using is crucial because it’s what makes the scanner compatible with some vehicle models and incompatible with others. Here are the five basic signal protocols and the vehicle models they are compatible with:
- SAE J1850 PWM: Compatible with Ford Vehicles
- SAE J1859 VPW: Compatible with General Motor vehicles and light trucks
- ISO9141-2: Compatible with European cars made between 2000 and 2004
- ISO14230-4(KWP2000): Compatible with some Asian vehicles
- ISO 15765-4/SAE J2480 (CAN-BUS): Mandatory for all US vehicles sold after 2008
Does the scanner work with third-party apps or devices?
As you have already seen, the best scanners work with both iPhone and Android devices. That they do by displaying their information on various third party apps including, but not limited to, Scan Master, Carista, or Torque. That’s a great feature to have as it means you won’t always have to look into the relatively tiny screen of the scanner.
However, while the majority of the models in this review are compatible with a third-party app, a small minority comes with apps of their own. You can log into these apps to scan, read, and even clear trouble codes across a wide range of vehicles. Though the problem with scanner-specific apps is that most of them aren’t as advanced or user-friendly as third-party apps.
Will the scanner merely display error codes or give troubleshooting tips as well?
Most inexpensive scanners merely display error codes when something is amiss with your vehicle. You’d then either have to consult their instruction manual or scour the internet to find out the meaning of the code. Only then you’d know what is wrong with your vehicle.
That isn’t the case with the top-rated scanners. Apart from displaying trouble codes, they recommend tips acting on which you can rectify the problem. You can, therefore, save a lot of time and effort which you’d otherwise have spent trying to unlock the code’s meaning.
6 Important OBD2 Scanner Features and Specifications
Following are the features and specs which are a must-have for the top-rated OBD2 scanners:
- Wide-ranging compatibility:
One of the best features of top-rated OBD2 scanners is that they don’t limit their compatibility to new OBD2 vehicles. Instead, these versatile products support the older OBD1 vehicles as well.
- User-friendly design:
Make sure your scanner comes with a backlit screen for you to read all the error codes at night easily. Its menu should be straightforward so that you don’t have to press multiple buttons to glean the information that you may need. So, just like when you’re searching for the best multimeter, you need to find a product that has an easy-to-follow interface.
- Live monitoring:
Devices that come with this feature monitor the performance of your vehicle’s engine constantly. That allows them to ensure that the overall performance of your vehicle remains optimal.
- Data storage:
Whether you are going to use it on your personal vehicle or multiple cars in a single workday, organized data storage is vital. It will let you keep a record of the problems you may have encountered with a specific vehicle in the past.
- Multiple connectivity options:
Most OBD2 scanners plug in directly to the OBD2 port in the vehicle. This has an advantage as such units don’t require batteries. However, if you want added convenience, you may want a model with Wi-Fi and Bluetooth connectivity options
- Settings access:
Apart from showing error codes, an OBD2 scanner must let you fine tune its settings, view different stats, control various sensors and warning lights.
Types of OBD2 Scanners
Here are the types of OBD2 scanners available on the market:
These devices are available in most auto parts stores and home improvement shops. You have to plug them into your vehicle’s diagnostic port – which exists beneath the dashboard on the driver’s side. They then display the ‘Diagnostic Trouble Code’ and help you remove that annoying ‘Check Engine’ light from your dashboard.
Available almost everywhere
Can both display and clean codes
Can’t offer much info on manufacturer-specific codes
In comparison with code readers, DIY scanners offer more information. Some of them are just like code readers in the sense that they display information on their screen. Others offer wireless connectivity using which you can get the information on your smartphone or computer. These devices let you read and clear diagnostic trouble codes (DTCs) and check your car’s speed, mpg, fuel consumption, and more.
Let you read and clear DTCs
Provide info about fuel consumption
Not as feature-rich as professional OBD2 scanners
Also known as professional OBD2 scanners, these devices diagnose and remove ‘Check Engine’ light. They also erase SRS and ABS error codes, give you information about the status of your car’s battery, its oil level, fuel consumption, and emissions. These scanners offer all this information in real-time and offer advanced features like ECU adaptation and ECU programming.
Provide everything you need in a scanner
Come with great warranties
OBD1 Scanners Vs. OBD2 Scanners
Here are the major differences between both these scanners:
Those of you who have used OBD1 scanners might tell that these devices have a manufacturer-specific interface. That isn’t the case with OBD2 scanners whose interface remains the same regardless of the type of vehicle you’re connecting them with.
While both the OBD1 and OBD2 scanners can be connected via a cord to a specific port under the driver side of your vehicle’s dashboard, the latter offers an added connection. You can connect high-end OBDII scanners via Wi-Fi or Bluetooth as well.
Since they are manufacturer-specific, OBD1 scanners come handy only for a specific type of vehicle (i.e., Ford, Volkswagen, etc.). That isn’t the case with OBD2 scanners, which offer (almost) universal compatibility.
Provided you go through the instruction manual of any OBD1 scanner, you’d come to know that it only supports vehicles manufactured in or before 1995. OBD2 scanners, on the contrary, are compatible with all vehicles which are produced in or after the following year.
OBD2 scanners can provide information about the check engine light, RPM, fuel consumption, speed, air/fuel ratio, battery performance, O2 sensors, and even smog testing. OBD1 scanners, however, only deal with emission systems and engine performance.
- Data storage and representation:
Both OBD1 and OBD2 scanners have built-in memory to store the history of previous error codes. But it is only with the OBD2 scanners that you can see that information in real-time and in graphical form.
How do OBDII Scanners Work?
To understand how OBDII scanners work, you’d first have to know about the working of your engine. That’s because the working of OBDII scanners is intertwined with that of your car’s engine. If you don’t have a clue about the working of latter, you may not understand how the former works.
How Does Your Car’s Engine Work?
As it’s the case, there are many sensors in our car’s engine, including pressure sensors, oxygen sensors, and engine knock sensors. Each of these sensors collects specific information that they then send to your car’s Engine Control Unit (ECU) in the form of signals.
After receiving the signals, the ECU adjust different elements of your vehicle’s engine operation – like air/fuel ratio, fuel injection, spark timing to ensure optimum operation. However, if the information is too far from the standard set point, the ECU generates a code known as the Diagnostic Trouble Code (DTC).
Once the ECU has generated DTC, your car’s ‘Check Engine’ light goes off. This light is an indicator that something is amiss with your car’s engine. It also serves as a warning that you shouldn’t drive your vehicle too far and have the problem resolved as soon as possible.
How OBDII Scanners Work?
Provided you have connected the OBDII scanner to a port underneath the dashboard on the driver side, it will show the DTC on its screen. You can then find out the meaning of the code by consulting the internet or going through the scanner’s manual to find out the cause of the problem.
Until that point, both the code readers as well as scanners perform the same function. However, while the readers do nothing apart from relaying codes, high-end scanners go the extra mile. Apart from showing error codes, they also give real-time data even when there is no problem with the engine.
Depending on the type of scanner you may have invested in (DIY or professional), the information might include air/fuel ratio, Anti-brake lock system, airbag problems, battery information, coolant temperature, the status of O2 sensors, and more. Some scanners also give tips to help you resolve the problem.
What can an OBD-II Scanner Do
Here’s what an OBD-II scanner is capable of doing:
- Carry out full-system diagnosis including brake system, transmission, fuel system and emissions
- Relays Diagnostic Trouble Codes (DTCs) generated by your Engine’s Control Unit (ECU)
- Provides information about the status of your car’s battery and its fuel injector
- Send commands to different systems of your cars to maintain its overall health
- Auto-correct any disturbances in the air/fuel mixture and vehicle’s ignition
- Ensure that your car’s IMMO (anti-theft) sensor is working
- Reads, displays and resolves SRS and ABS trouble codes
- Checks smog, freeze frame and vehicle specs
- Generates personalized user reports
- Turns off ‘Check Engine’ light
Issues an OBD-II Scanner Can Detect
As stated earlier, high-end OBD-II scanners can detect multiple things that may be wrong with your car. They can let you know whether your vehicle’s air/fuel ratio is optimum or not, whether it is consuming too much fuel, and is the temperature of its coolant beyond the pale.
On connecting this scanner to the port beneath your dashboard, it will let you know about the readiness of your vehicle for fuel emissions and smog test check. These devices also relay info about any problem with your car’s EVAP system, with some of them capable of correcting your steering angle.
Aside from that, these scanners can detect issues (if any) with the performance of your battery. They can tell whether there is any problem with the O2 sensors. You can also count on them to let you know whether your car’s ABS is working properly and if there is any issue with the airbags.
To further sweeten the deal, these devices will make you aware if there is any problem with your engine timing, engine speed, and RPM. Some of them go as far as to check electrical connections with their built-in multimeter to reveal burned-out cables and pesky electrical shorts.
6 Benefits of Owning a Code Scanner
Here are the benefits you can garner by owning a code scanner for your car:
Brings down repair costs
What do you think would happen if you diagnose the problems in their early stage? You’d be able to resolve the issue without having to spend big bucks.
Also, the early diagnosis of the problem will prevent it from getting worse and causing a secondary malfunction – like detecting misfiring before it could do damage to the catalytic converter.
Optimize fuel economy
Does your OBDII scanner display the P0171-P0175 error code? Then congratulations are in order as you can this ‘Oxygen Sensor’ code will result in the optimization of your vehicle’s fuel economy.
Scanners that display this error code then use it to calibrate your vehicle’s ECU. This allows them to decrease the emissions of your vehicle and optimize its fuel economy.
Prevent engine misfiring
There are many reasons your engine might be misfiring: lack of voltage at the coil, damaged spark plugs, vacuum leakage, weak fuel injector, and worn-out valve seals.
Whatever the cause might be, driving with a misfiring engine can be extremely dangerous. Scanners track (and resolve) this problem by observing the speed of the car’s crankshaft when the engine is running.
Identify the problem’s root cause
As you might have seen in the reviews section, most OBD2 scanners come with a ‘freeze frame data’ feature. This option lets you pause the device as it is relaying live data on its screen.
As a result, once you’ve paused the scanner at a specific instance, you can pinpoint the root cause of the problem. You won’t have to spend hours trying to get to its bottom.
Help your car pass DEQ test
Most states require vehicles in their jurisdiction to pass the DEQ test before permitting them to run on roads. While newer vehicles quickly pass this test, older vehicles tend to get stuck.
However, if you have an OBD2 scanner, you can identify any problem that may hamper your vehicle’s performance in the test. You can then get the problem fixed to increase your chances of passing the DEQ test.
Avoid costly mechanic trips
Have you ever driven your vehicle to a mechanic because its ‘Check Engine’ light was on? Then you’d know that in nine out of ten cases, the issue was so tiny that you could have fixed it yourself.
With an OBD2 scanner, you can pinpoint the issue without having to consult the mechanic first. If necessary, you can still visit the mechanic, but not for an issue that you could fix on your own.
How To Use A Diagnostic Code Scanner In 3 Steps
Follow these steps to use your scanner correctly:
- Step 1: Locate the OBD port
As stated earlier, the OBD (on-board diagnostics) port is used to connect the scanner to your vehicle’s computer. You should be able to locate it under the dashboard of the driver side quickly. It can be found under the steering column.
- Step 2: Connect the scanner to the OBD port
Push your driver seat back and hunch under the steering wheel. Remove the cap hiding the OBD port and insert the scanner’s connector into the OBD port. Make sure that the connection is snug and the connector isn’t loose.
- Step 3: Enable the scanner
Provided your unit didn’t power on automatically, manually turn it on. Then, turn your vehicle’s ignition switch and set it at ‘accessory position.’ Follow the on-screen prompts to select the model of your car and its manufacturing year.
Do’s and Don’ts of Using OBD2 Scanners?
Following are the do’s and don’ts of using these scanners:
- Turn off the power of your vehicle before connecting the scanner
- Wait for the scanner to start after switching your car on automatically
- Only input all the data when the scanner is ready to process it
- Give the scanner enough time to read and scan your car’s diagnostic system
- Switch off your vehicle and disconnect the scanner once you’re done collecting the codes
- Don’t try to forcefully insert the scanner’s connector into your vehicle’s OBD port. Its pins may bend if you apply too much force.
- Don’t switch off your car while you’re using the OBD2 software. This might erase all data and can even corrupt the software
- Don’t start using the OBD2 scanner without consulting its instruction manual first. As some devices have different operating procedures than others.
How to Read and Understand OBD Codes
Once you have connected your scanner to your vehicle using the abovementioned process, turned the vehicle’s ignition on and started the scanner as well, use the following procedure to understand the meaning of various OBD codes:
- Step 1: Enter your car’s Vehicle Identification Number:
Some scanners might require you to insert your vehicle’s make, model, VIN, and engine type. The type of information they may require varies depending on the type of scanner you may have purchased.
- Step 2: Locate the menu:
Once the scanner starts up, locate its menu. Specifically, look for a menu bar like ‘Codes’ or ‘Trouble Codes.’ Once you click on it, you may be presented with a few options like Engine, Transmission, Brakes Airbag, etc.
Tip: On selecting an option, you’ll be presented with Active codes (errors that are keeping the ‘Check Engine’ light on) and Pending codes (those that are set to become active in the coming minutes).
- Step 3: Understand the codes:
Each code will start with a letter designating the system of your car that may be malfunctioning. These letters include:
- P: This letter means powertrain and covers engine, ignition, transmission, fuel system, emissions, and more.
- B: This letter means body and covers power seating, power windows, seat belts, airbags, and more.
- C: This letter means chassis and covers the Anti-lock braking system, axles, brake fluid, and more.
- U: This letter covers the remaining aspects of your car.
- Step 4: Learning what the codes mean:
A specific code will look something like P0xxx or P1xxx. While the first letter tells you the part of the car where the problem lies, the second tells about the subsystem, and the remaining three digits refer to the specific problem area. Consult this OBD code chart to learn what the problem is.
FAQs and Answers
- Q: Will a diagnostic tool work on non-US cars?
A: Regardless of whether you’re using an OBD or OBD2 scanner, you should rest assured with the knowledge that both of them work on compatible non-US cars. The key word here is ‘compatible’ – so you should make sure before purchasing a scanner whether it will work with the model of the car you’re driving. As none of the diagnostic scanners you see on the market offer universal compatibility.
- Q: My car is older than 1996. Can I use a scanner tool?
A: OBD scanners work with models that were manufactured in or before 1995. OBDII scanners, however, work with all cars manufactured in or after 1996. That means you can use an OBD1 scanner with your car.
- Q: Will OBD2 scanners drain the battery?
A: Poorly designed OBDII scanners might completely drain your vehicle’s battery if left plugged into the OBD port for hours. That’s why we recommend that before you start driving the car, detach the scanner from the port under your dash.
Best Obd2 Scanner Comparison Chart
|PRODUCT||Price||Weight (ounces)||ABS and SRS diagnosis?||Reads/erases Check Engine Light||Warranty||Language Support|
|BlueDriver LSB2 Bluetooth Pro OBDII Scan Tool for iPhone & Android||$$$$||2.08||Yes||Yes||1-year||1|
|INNOVA 3160 Diagnostic Scan Tool||$$$$$||32||Yes||Yes||1-year||3|
|FOXWELL NT301 OBD2 Scanner||$$$||17,6||Only ABS||Yes||1-year||5|
|Autel AutoLink AL319 OBD2 Scanner Automotive Engine Fault Code Reader CAN Scan Tool||$||6,2||No||Yes||1-year||7|
|ANCEL AD310 Classic Enhanced Universal OBD II Scanner Car Engine Fault Code Reader||$||11,4||No||Yes||3-year||2|
|NEXPEAK OBD2 Scanner||$$||24,8||No||Yes||3-year||8|
Why would anyone invest their money in an OBD2 scanner when they can just consult an auto-mechanic whenever something goes awry with their vehicle? Apart from being a one-time investment, the best OBD2 scanners give you the information that you don’t know you need until you have it.
Need examples to believe in this claim? Then check out our OBD2 scanner reviews. Apart from helping you turn off that troubling ‘Check Engine’ light, these devices let you gauge the status of your car’s battery and whether or not its O2 sensors are working correctly.
Aside from that, since these devices perform actively, they make you aware of a problem before it even rears its ugly head. That information saves you from that dreaded scenario of being stranded in the middle of nowhere and without any knowledge of what has gone wrong with your vehicle.