Understanding OBD2 Scanners - Guide
Diagnosing car problems yourself can save you money. The problem is there are hundreds of OBD2 scanners in the market; which makes it difficult for DIYers to choose the best OBD2 scanner. We understand that this process can be overwhelming for most car owners. Especially if you are just starting out with DIY auto repair.
You may be surprised to know that choosing the best OBD 2 scanner is a challenger even for auto mechanics. In this article, we will break down OBD-II scanners into several categories. This will help you choose the best scanner based on your troubleshooting needs.
Choosing the best OBD2 scanner depends on two main factors. Ask yourself these two questions:
- What are you trying to diagnose?
- Check Engine Light,
- ABS Problems
- Airbag / SRS Light
- Transmission Problems
- Program Modules
- What is your budget?
- Under $50
- Under $100
- Under $200
Keep these factors in mind as you read this guide. As you probably already have found out, OBD2 scanners can cost from as little as $15 all the way up to over several thousand dollars. We have had a chance to use several scanners including professional and even dealer level scanners.
To make it easy for you, we are going to break OBD-2 scanners in three main categories.
We will start with the most basic and cheapest OBD2 scanners. These scanners are known as code readers or generic OBD2 scanners. They can retrieve data from the Engine Control Unit (ECU). Which means you can retrieve codes that trigger the Check Engine Light and Service Engine Soon. They are also the cheapest OBD2 scanners because they don't need to be vehicle specific, access other modules or provide any coding capabilities. We will also take a look at multi-system OBD2 scanners and what they offer. We will end with the professional diagnoser scanners that provide similar troubleshooting and functionality that you often can only get at the dealer.
For each category, we will make recommendations based on our hands-on experience, research and current OBD2 scanners that are popular.Back to top
1. Level 1: Basic OBD2 Code Readers and Scanners
These are known as basic OBD2 code readers. They allow you to read, clear codes and reset the check engine light. Simply plug into the OBD-2 port and read the code. They show you a fault code and some scanners even tell you what the code means. Regardless of what description you get from the scanner, write down the code and find out what it means for your particular make.
Bluetooth OBD2 scanners generally fall into this category, especially the adapters that have ELM327 chip. These Bluetooth OBD2 scanners are capable of showing your live sensor data, engine RPMs, 0-60 mph times, etc. As far as car diagnosis goes, these units are only able to read, clear engine fault code and reset the check engine light.
Here is a list of what you can do with these scanners:
- Read Fault Codes from Engine Control Unit
- Determine why Check Engine Light is on.
- Erase Check Engine Codes
- View Freeze Frame Data
- Display live sensor data from ECU
- Can not access other modules.
- Can not read codes from ABS, SRS, transmission etc.
- Can not troubleshoot TPMS
- No programming or coding
These scanners cost as little as $15 USD. We also have seen basic OBD2 scanners priced over $100 at local auto parts stores. There is no need to spend $100 for a basic OBD2 scanner. To read and clear Check Engine Light and Service Engine Soon light a $15 OBD2 scanner will get the job done. The more expensive OBD2 scanners may show you live oxygen sensor data, intake air temperature, and a few other parameters.
With that said here are our top picks for this category.
1. Autel MaxiScan MS300
What you need: Autel MaxiScan
- This is one of the most popular OBD2 scanners. Probably because it is the cheapest OBD2 scanners on the market. We would not recommend the Autel MaxiScan MS300 for a couple of reasons. Based on our hands-on experience we noticed two issues with this scanner.
- The scanner failed to reset the Check Engine Light on several occasions. It required that we repeated the procedure to clear fault codes at least twice.
- The device doesn't show a description of the error code. It only shows you the code number, for example, P0301. Not a major drawback because you can do an online search as to what that fault code means. It is nice to see a quick description of the fault code right away.
- There are better alternatives to Autel MaxiScan MS300 model.
2. MS309 OBDII Car Diagnostic Tool
- If you are looking for one of the cheapest and best OBD2 scanners a good choice would be Autel MS309. Not only is it an affordable OBD2 scanner that is easy to use but also offers several amazing features such as:
- Read and Clear Fault Codes including Check Engine Codes.
- Retrieves generic (P0, P2, P3 and U0), manufacturer specific (P1, P3 and U1) codes and pending codes.
- Views freeze frame data.
- Display monitor and I/M readiness status (emissions).
- Retrieves vehicle information such as VIN.
- Supports all 1996 and newer vehicles.
To learn more about Level 1 OBD2 scanner read continue to this article: Basic OBD2 Code ReadersBack to top
2. Level 2: Multi-System OBD2 Scanners
If you work on cars frequently or are trying to troubleshoot problems other than the check engine light, you need a multiple system OBD2 scanners. These scanners not only can reset the check engine light but they can diagnose problems with the Anti-Lock Brakes, Airbag system, Transmission and Tire Pressure Monitoring System.
A full system OBD2 scanner will be able to read, clear and reset fault codes on multiple systems and stream live data, but they can not perform any coding or activate actuators. A full system OBD2 scanner is the way to go if you work on cars frequently. One trip to the dealer could save you enough money to buy one of these scanners.
Even if you haven't used a full system OBD2 scanner before don't worry. They are very easy to use and function the same as the basic OBD2 code readers. The main difference is that they can access another system on your car, not just the ECU.
- Read/Erase Check Engine Codes
- Read/Erase ABS Fault Codes
- Read/Erase Airbag / SRS Codes
- Troubleshoot transmission problems
- View Sensor Live Data
If the scanner is made to work on many makes and models, it may not be able to access as many modules compared to a Level 2 scanner that is designed to work on one particular make.
- No Coding
- No Programing
Most level 2 scanners that we have used and researched range in the $150-$250 price range.
1. Launch Creader
Check Price: Launch Creader Scanner
It covers most vehicle makes. Works on European, Asian and domestic cars. Provides coverage for four vehicle systems:
- Engine / ECU
To learn more about Level 2 scanners read this article: Multi-system OBD2 scanners
2. Universal Foxwell NT624
Provides in-depth vehicle troubleshooting of most systems. It works on American, Asian and European vehicles. Operates on all cars from 1996 to present.
- Airbag / SRS
- Automatic Transmission
- Instrument Cluster
- Climate Control
- Power Steering
- Engine / ECU / Check Engine Light
Works on cars, SUVs, trucks, and minivans.
3. Autel MD802
Provides coverage for four vehicle systems:
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3. Level 3: Professional OBD2 Diagnostic Scanners
Professional diagnostic scanners provide similar functionality to the scanners used at your car dealerships. These are meant for mechanics that operate auto repair shops. If you are a DIYer you probably don't need to spend thousands of dollars on a professional diagnostic scanner.
Here are the main benefits of professional diagnostic scanners.
They can diagnose all system and control units. A complete system expert scanner is not limited to one make but works on most car brands including Honda, Toyota, BMW, VW, Mercedes, Porsche, Ford, Chevrolet, etc.
Not only can they diagnose the Check Engine Light, but they can also read and clear fault codes from systems such as:
- Anti-Lock Brakes
- Traction Control
- Climate Control
- Entertainment, Navigation
- Stability Control
- Engine / ECU
- Yearly upgrades cost money
Many car manufacturers require that certain modules can only be coded by the dealer. Professional scanners will not be able to code replacement of certain modules if the coding can only be completed by the dealer.
The cheapest professional level scanner starts at around $800.
To learn more about these scanners read our article on choosing the best Level 3 Professional Level Diagnostic Scanner.Back to top
Diagnostic scanners can save you money. Level 1 and Level 2 scanners are easy to use even if you have never been trained on how to use them. We understand that choosing the best OBD2 scanner can be a challenge. To find the best OBD2 scanner, you need to ask yourself these two questions:
1. What am I trying to diagnose?
- Check engine light. Read, Clear Engine Codes
(Even a basic $15 OBD2 code reader can read, erase engine fault codes and reset the check engine light. Don't need to spend hundreds if this is all you are trying to achieve.)
- Emission Readiness Status
(Will help you find out if the car is ready to pass emission test.)
- ABS Anti-Lock Brakes
- Automatic Transmission
- Airbags / SRS / Restraint System
(Figure out why the airbag light is on)
- TPMS Tire Pressure Monitoring System
(Find out why the TPMS light is staying on.)
2. How much am I willing to spend?
- OBD2 Scanners in this range provide data from the Engine Control Unit (ECU). Which means they can read, clear fault codes and Check Engine Light.
- OBD2 Scanners in this price range can read and clear fault codes from the Engine Control Unit, ABS, SRS, Airbag, and transmission.
- Professional Diagnostic Scanners that provide in-depth troubleshooting of all vehicle systems. Similar functionality as the scanners used at car dealerships.
We hope that after reading this article, you understand that it doesn't make sense to ask yourself "What's the best OBD2 scanner?" without trying to figure out what you are trying to accomplish. It also doesn't make sense to read OBD2 scanner review websites and blogs often posted by people who have never used an OBD2 scanner in their life.
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Posted by wayne w. on Aug 10, 2017 @ 10:55 am
I was going to take my 2013 dodge van into the dealer to have my spark plugs change on a 3.6L engine , but after watching your video I did it myself and save myself a lot of money. Keep making those great video. Great job guys.
Posted by wpatters1229 on Oct 15, 2017 @ 19:10 pm
i have the cheap scanner. If I clear a code and then take it into get tested for smog will it show the tech that I just cleared a code? If so will that keep me from passing? This is CA
Posted by MBFanatic on Oct 24, 2017 @ 16:29 pm
When you clear the codes, all the monitors are reset. It takes two to three days worth of driving to get all the monitors ready. If you have more than one monitor Not Ready, you will fail. In most states at least. Probably CA too since they are so strict on emissions. In most cases you will pass with only one monitor being Not Ready.
If you take your car for emission right after you clear the codes. You will surely fail.
Posted by Amanda on Nov 21, 2017 @ 04:31 am
I have bought Launch CR4001 code reader before. It is well worth buying because of the high quality. It works on my Ford perfectly. In fact, the design is considerate – the cable attached to the device and the other end of the cable plugged into the OBD port on my vehicle. The instruction described on the user manual is clearly, which are really easy to understand. I can easily check if the engine emissions reach the standard.
I don’t have to always go to automotive services cause this tool can help me solve some small problems. What satisfied me a lot is the metal dome designed keys which are sensitive and easy to operate with great feelings. Maybe you can have a try.