Reddit Reddit reviews Autel MS300 Universal OBD2 Scanner Car Code Reader, Turn Off Check Engine Light, Read & Erase Fault Codes, Check Emission Monitor Status CAN Vehicles Diagnostic Scan Tool

We found 62 Reddit comments about Autel MS300 Universal OBD2 Scanner Car Code Reader, Turn Off Check Engine Light, Read & Erase Fault Codes, Check Emission Monitor Status CAN Vehicles Diagnostic Scan Tool. Here are the top ones, ranked by their Reddit score.

Automotive Tools & Equipment
Code Readers & Scan Tools
Diagnostic, Test & Measurement Tools
Autel MS300 Universal OBD2 Scanner Car Code Reader, Turn Off Check Engine Light, Read & Erase Fault Codes, Check Emission Monitor Status CAN Vehicles Diagnostic Scan Tool
TURN OFF CHECK ENGINE LIGHT: MS300 check engine code reader can read, clear generic, manufacturer-specific and pending codes. It enables you to figure out why CEL is on like a pro and turn off check engine light instantly after proper repair.MECHANIC APPROVED: MS300 OBD2 scanner works with most OBDII compliant(OBD2 protocols: KWP2000, ISO2000, ISO9141, J1850 VPW, J1850 PWM, and CAN) sedans, SUVs and light trucks post-1996 for US cars, post-2000 for EU-based and Asian cars.DIAGNOSE IN SECONDS: MS300 auto code reader features easy to use 2 button design to read, clear DTCs to help home mechanics locate car problems fast. With an intuitive interface and easy-to-read backlit screen, this diagnostic code reader is easy to use.SMOG CHECK: MS300 car code reader retrieves I/M Readiness status to check emission-related systems like misfire monitor, fuel system monitor, comprehensive components monitor, O2 sensors, EVAP to help your vehicle ready pass the annual smog check.NO BATTERY NEEDED: MS300 OBDII scan tool communicates with vehicles through standard 16-PIN OBD2 cable and it’s powered by vehicle directly- no battery needed. Please follow the correct usage order: Engine off- Plug MS300 in- Turn Ignition On.RETRIEVE VIN NUMBER: MS300 engine code readers can retrieve VIN (Vehicle Identification Number) on 2002 and newer vehicles supporting Mode 9 for quick vehicle identification and cut time spent locating the cause why the check engine light is on.RISK-FREE PURCHASE: Autel MS300 vehicle code reader comes with 30 Day Refund or Replacement and 12 Months US Seller Support. Should there be any concerns, please contact us directly via [email protected] to get hassle-free after-sales services.Retrieves generic and manufacturer specific Diagnostic Trouble Codes (DTC), includes definitions lookup software on CD and displays DTC definitions on screenFeatures an easy-to-read backlit LCD screen, multilingual menu and DTC definitions and standard 16-pin OBD-II connector--no additional cables are neededRetrieves VIN (Vehicle Identification No) on 2002 and newer vehicles that support Mode 9Supports the CAN (Controller Area Network) protols and all other current OBD-II protocolsWorks with most OBD-II compliant U.S., European and Asian vehicles (OBD-II is standard on all cars sold in U.S. post-1996)
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62 Reddit comments about Autel MS300 Universal OBD2 Scanner Car Code Reader, Turn Off Check Engine Light, Read & Erase Fault Codes, Check Emission Monitor Status CAN Vehicles Diagnostic Scan Tool:

u/IMLOwl · 127 pointsr/AdviceAnimals

Get one of these, plug it into your car in the port hidden under your steering wheel, download app called Torque, get error code, google error code, see if it's something you can fix yourself (often it is).

Edit: These only work on Android. You can buy dedicated units (also cheap) or you can buy an iOS version that costs 4x as much. Similarly cheap priced models claim to work on iOS, but I have yet to see anyone actually get one of them to work.

u/MacEnvy · 10 pointsr/IAmA

>It is normally an $80 minimum charge at a shop to get your codes pulled, and it only takes a second.

Or you can buy a reader for $20.

u/NoOneLikesFruitcake · 9 pointsr/LifeProTips

They go even cheaper so long as you don't mind futzing with the port and cable. Bluetooth would be amazingly more convenient though.

u/PotatosAreDelicious · 7 pointsr/Justrolledintotheshop

More like $15. Here and Here

u/KPexEA · 7 pointsr/Porsche

Buy an OBD-II reader. You can pick one up from or a local shop for about $20. Plug it in and download the error codes.

This is the one I have, works fine on my 996tt and ML500.

u/PNWTim · 6 pointsr/LifeProTips

Or spend Less than $20 on a real scanner without risking frying your $2000 ECU. If you plan on doing to work yourself spend a little more and buy one that allows you to view live and freeze frame sensor data.

u/IamRandallStevens · 5 pointsr/pics

I'd like to add

  1. youtube. There is a video for just about everything. (If nothing else you'll see how easy...or how ridiculously hard it is.

  2. $20 engine code reader

    all 1996 (IIRC) or later cars must have easy access to the onbaord computer too, usually down by your feet.

    This $20 device plus google enables you to figure out the problem and if you can handle it yourself.
u/Aterners · 5 pointsr/BMW

Here's the link, it's only $16

Autel MaxiScan MS300 CAN Diagnostic Scan Tool for OBDII Vehicles

u/trigger_control · 5 pointsr/Cartalk
u/zx2gamer · 4 pointsr/MechanicAdvice

Don't get something old from the 80's or 70's. it'll just make getting parts harder.

If you want a reliable beater that will be easy to repair get a 90's Honda. They are simple to work on, parts are plentiful, and as a daily driver they get amazing mileage. If you yet an obd2 model (96 and newer) get one of these so you can scan the codes.

u/Uranium234 · 3 pointsr/sandiego

I have my office in sorrento valley. If you want to drop by tomorrow morning I can let you read the code or possibly borrow my reader.

I have this one

u/NeptuNeo · 3 pointsr/LosAngeles

I recommend buying from Amazon a diagnostic code reader so you can read the check engine codes yourself and verify what the garage is telling you. I bought one a few years ago for only $15 and it works great, there are newer/ better ones now but here is the one I use:
[Diagnostic Scan Tool for OBDII Vehicles] (

u/eck- · 3 pointsr/Cartalk

It's worth getting your own. I have an Autel similar to this one. I've only used it once and it retrieved the code no problem.

u/vinnyvecchio · 3 pointsr/cars

That's what I assumed unfortunately.

I got a $20 scanner on Amazon, and it can check inspection monitors. It's a simple tool, but it will go through the list of monitors (evap, cat, etc.) and tell me if it is ready or not.

I guess I will just have to hope for the best if I don't see any CELs. Thanks for the answer!

u/WRSaunders · 3 pointsr/explainlikeimfive

It's easy:

  1. Find out why the light is on. This could be a loose gas cap or a real problem. There is a $14 code reader gizmo for this.

  2. Fix the problem. This of course depends on what th problem is.

  3. Reset the MIL (that's the real name of the "check engine" light). Your reader gizmo can also do this.
u/Undercover_Hitler · 3 pointsr/AskMen
  • Learn how to change a tire. Do it in your driveway or in a parking lot on your own. It is a lot better to know how to do it right when you need to. And it is much easier to learn how on a warm sunny day than on the side of the road in the rain, or the middle of the night.

  • Keep a tire pressure gauge on you. If your tires appear low, check the pressure. Tip: Sheetz gas stations (at least the ones in Virginia) have free air (most gas stations do). Their systems have a digital pressure setting and an auto-cutoff. Just set the pressure, and it will stop filling when it gets there. Otherwise use your pressure gauge to dial it in. Most cars will feature the tire pressure for front and rear tires on a sticker in the front door frame.

  • Water will work as coolant in the summer. If it is colder outside, you will want to buy antifreeze. Most gas stations will sell it.

  • If a warning light on your dash comes on (check engine, oil light, alternator light, etc) you will need to get it checked/fixed soon. Check engine lights can sometimes be nothing (sometimes it is just a loose gas cap), but it is always good to get it checked. More on that in a minute. If a warning light on your dash starts flashing, that is a serious problem. Pull over, turn the car off, and call a service station

  • You can save yourself some money by getting an OBD2 Reader. These read your check engine codes and tell you why your check engine light is on. Some shops will do this for you for free, some will charge $20. Most corporate owned auto stores will let you borrow theirs in exchange for your drivers license. Personally, I say just drop the $20 and get one, it saves time later on. They sell ones that are much more expensive, up to thousands of dollars. You don't need these; these give "live" data of the car's sensors and other things that won't help anyone other than a mechanic. A small $20 one will read the code and probably clear it if you want.

    Simple run down on how to use them (should be in the instruction book). 1. Plug it into the car, with the car turned off. (The plug will almost always be under the dash) 2. Turn the key to the ON position. (Do not start the car, just one click before it. Like if you wanted to turn the radio on but not start the engine) 3. The code reader will usually say READING for a few seconds and give you one or more codes. They will look something like P0430. Cheap readers usually have books with them that will tell you what they mean. More expensive ones ($100-$200) will define the code. If you don't have the book, just google the code.

    Depending on the code, you may or may not understand what it means. This is okay. If you google the definition of the code, you will almost always find someone describing the general idea of what is going on. Again, you might not be able to use this info to repair the car yourself, but it can give you an idea of how serious a problem is, and may prevent you from being ripped off by mechanics.

  • Anticipate maintenance and repairs. Tires are expensive. Thankfully, they don't need to be replaced all that often, but changing 4 tires at once can easily be $300 bucks for cheap new tires. Avoid used tires. Keep $100 saved up to get the oil changed. Newer oils need to be changed less often, but the shop should advise you when to come back. (I'm assuming you aren't planning on changing your own oil any time soon) Nothing is worse than knowing your oil is dirty and overdue for a change but not having the money to make it happen, and old dirty oil will shorten the life of your engine.

  • Every 6-8 months, when you get gas, go into the gas station and buy fuel system cleaner. It will look similar to this. Simply pour the entire bottle into your gas tank and then fill up your tank to the top. Also, and this is very important! DO NOT PUT THIS IN A DIESEL VEHICLE

  • Finally, find a good mechanic/service station. Ask locals around your town. Check reviews. The difference between a good one and a bad one can be hundreds, if not thousands. Before I learned about cars, I went to several mechanics for my first car.

    One never updated me on their progress, charged super high prices, and recommended unnecessary repairs. Then I went to one that would come out and talk to me 2 or 3 times throughout the repair (giving me updates, letting me know of other problems he noticed, etc), he would never perform an additional repair without taking me into the shop and showing me exactly what he was talking about. At one point, he ordered brake parts from down the street because I thought I needed new parts. Turned out it was a whole different issue with different parts. He happily sent them back, free of charge to me, and walked me through what he was going to do. I still take my cars to him when they have "gremlins" that I can't figure out. Usually they charge a pretty big service fee per hour, but from the very first time he charges me 1 hour less than whatever it takes him. His reason is always "I wanted to figure it out as bad as you did. Forget the money, this thing became my puzzle."

    But I've been rambling on that. Point is, find a good mechanic and stick with them. It will make a huge difference.
u/SugarWaterPurple · 3 pointsr/Cartalk

I have the same scanner, it's not very good. They use a knockoff ELM327 chip which doesn't work very well.

You're better off with something like this:

I have both and never use the bluetooth one, the standalone unit is much more convenient and reliable.

u/woofwoofdog99 · 2 pointsr/Jeep

I've got a 2011 wk2 that's had more than its share of problems and this thing was well worth the $16.

But yeah, with the factory warranty you won't pay a penny to have whatever the problem is fixed.

u/habeemred1 · 2 pointsr/newjersey

So just disconnect the negative for a few minutes and drive around? I bought a an ODBII reader that worked for another

I am hoping with disconnecting the negative on the battery and driving around with this plugged in that I will see evap ready. I found it on a toyota4runner forum that some guy used it when he had same issue until it read evap ready. It will arrive Sunday and than I will play around and hope on day off I will be able to pass inspection

u/Rishodi · 2 pointsr/personalfinance

This is a great post, but I do have a couple of counterpoints to make:

  • Don't change your car's oil every 3000 miles. Follow the owner's manual instead. Most cars being driven today only need oil changes every 5000 miles.

  • You can buy an ODB-II scanner for as little as $30, but many auto parts stores (Autozone, Advanced Auto) will pull the codes for you without charge.
u/brock_lee · 2 pointsr/AskReddit

Get yourself a $20 OBD-II code reader which can be used to clear the codes. Maybe borrow one first at AutoZone, to clear the codes, and see how long it takes for the CEL to come back on. If it's more than a, hour or so, take your new reader when you go for the smog test, and clear the codes right before. Maybe it'll get past if the CEL stays off long enough.

I have this one, works great:

u/brianinswfla · 2 pointsr/Cartalk

It won't help you now but for the future you should get a reader. There is a cheap one ($17.10 with Prime) on Amazon. I have had it for awhile and it comes in very handy.

u/jevan027 · 2 pointsr/Miata

Yes. Its illegal for them to clear them in a lot of states now. Personally, I just bought a cheap scanner off amazon that works fine. But if you ask them to 'loan' you the trouble code scanner they wont be there to supervise you. You might have to hand them your license while you do it though.

u/Alex-Gopson · 2 pointsr/Audi

If you go to Amazon and type in "OBD2 scanner" you'll get tons of different results. They have all kinds of scan tools nowadays. The more expensive ones with really advanced features can even cost thousands of dollars and look like freaking Ipads!

But a basic $15 scanner like this is still great to have. It's super simple to use. You plug it into your cars OBDII port (located in the driver's side footwell, usually somewhere near the hood release latch.) Then flip your key to the "on" position (don't turn the engine on, just turn on the ignition such that you can use the car's accessories and unlock the steering column.)

From there you can pull codes as well as erase them. The scanner will come with more detailed instructions but it's pretty self-explanatory. The thing only has 2 buttons so if you can use a computer or cell phone it shouldn't be a challenge.

u/DeterrenceTheory · 2 pointsr/MechanicAdvice

I bought this one about a year ago, no complaints. Cheap. Easy to use. However, it doesn't look like it's sold directly by Amazon anymore, and I'm sometimes wary of the overseas third-party sellers. In general, you probably won't go wrong with any of the readers sold on Amazon with hundreds of good reviews.

u/AndrewWaldron · 2 pointsr/Louisville

Exact one I bought. Very simplistic but it worked for reseting my codes. Now, what you may encounter, is the CEL will come back on because whatever tripped the CEL in the first place will likely trip again if you've removed a component. Just a heads up.

u/boxerswag · 2 pointsr/subaru

This is a very common Subaru code. It ranges from seemingly "unfixable" (i.e., reflash the ECU to ignore it), catalytic converter replacement, rear O2 sensor, exhaust leak, all kinds of stuff. I wouldn't worry too much unless other symptoms/codes appear. My car throws a P0420 about every 1000-2000 miles (edit: and still gets high 20's average and drives fine).

In the meantime, buy one of these so you can read and clear your own OBD-II codes.

u/ToGTIorNotGTI · 2 pointsr/Volvo


Like this one here

u/Montagge · 2 pointsr/MechanicAdvice

First one I ever got was an Autel MaxiScan M300. It doesn't suggest fixes, but that's what I used google for! Worked great on ever car I used it on

edit: I still use it when all I want to do is read or clear codes and not read live data

u/GardenGnomeOfEden · 1 pointr/AdviceAnimals

You should get an OBDII diagnostic tool. I bought this one. You plug it in under your dashboard and it gives you a code which you can look up to see what is wrong with your car. It also gives you the option to cancel the check engine light.

u/DaveCootchie · 1 pointr/MechanicAdvice

this one has live data from the car, $33

This one only reads codes but gives you the definition $18

This just reads codes, nothing else. $15

If they quoted you $3200 its probably a professional scan tool, those can read anything going on in the cars computers and even take control of stuff too. If you just want to see what's causing the check engine light and of the above 3 would work.

this last one is more expensive, but it can read obd2, abs, and air bag codes. Pretty much everything the big $3k unit does.

u/noobidiot · 1 pointr/cars

they are pretty cheap...theres also cables you can hook up to your android phone and do the same thing

u/mirthilous · 1 pointr/AdviceAnimals

I seriously recommend buying your own code reader. Amazon has them for as little as $16 right now. With a little Google research, you are much better armed with information if you need to go to a shop to get your car fixed. Here is an example:

u/iamtehstig · 1 pointr/saab

You can now get a decent one on Amazon for under $20 shipped. I have two of them.


u/fermion72 · 1 pointr/IAmA

Here you go.

I don't know what CAN means, but the one I linked to seems to support it. Mine turns off the check engine light if it's on, and it reports the codes, which I then look up online.

u/StopNowThink · 1 pointr/saab

Buy this:

Autel MaxiScan MS300 CAN Diagnostic Scan Tool for OBDII Vehicles

In the mean time, go to your local auto parts store and get the codes read.

Full synthetic every 3k, premium gas, pcv update. If your vacuum lines show any aging or are cracked, replace them all. Don't forget to check your spark plugs.

BTW every Saab after 98 has a turbo. For 9-5s of that year they are either base (2.3t), SE (3.0t), or aero. Sedan, or wagon.

u/MHerboth · 1 pointr/MINI

Either an OBD reader this or in the US certain stores can read codes for free like autozone, don't know about the UK though.

They make bluetooth readers too if you have a smartphone and or want to leave it plugged in.

u/yotimes · 1 pointr/BmwTech

Got a smart phone?

Reader 1

Reader 2

I don't know how shipping works to Canada, but it isn't too expensive of a product, and I am sure you can find it locally. It is a very handy tool.

That sounds like pretty good fuel econ lol. With my tune my 335i gets around 14-18 MPG

u/JLee50 · 1 pointr/Showerthoughts

If you ever want one that doesn't need a phone, that works well too.

u/Workasaurus · 1 pointr/Random_Acts_Of_Amazon

OBD II Diagnostic Scanner

This is an error code scanner for automobiles made within the last 15 years or so. When plugged in to a vehicle, it'll read error/check-engine codes and even tell you what problem/definition that code corresponds with.

It's a tool that my SO and I need every so often, and I'm sure our friends do as well. I'd like to save everyone the time of taking their cars to shops just to check engine codes. Some shops charge for this service, even though the code might report something as simple as a loose gas cap.

u/garatron · 1 pointr/Volkswagen

Invest in a code reader, that'll tell you what the problem should be. I have this one and it works fine on my Jetta. Also, tuning chips on non-turbos hardly add any power, like 5-10hp which wouldn't be noticeable.

u/Goodefornothing · 1 pointr/cars

I bought the cheapest one off of Amazon (~$15) and it has served me faithfully for 3 years and has no learning curve.

Edit: This one.

u/Ceorl_Lounge · 1 pointr/mazda

Autel MaxiScan MS300 CAN Diagnostic Scan Tool for OBDII Vehicles

Bought one of these two years ago after my Jetta started throwing codes. Cheap, simple, easy to use, I just look up the codes online after scanning.

u/paranoidtandroid · 1 pointr/AskSF

Autel MaxiScan MS300 CAN Diagnostic Scan Tool for OBDII Vehicles by Autel

u/thesandiegan · 1 pointr/AskMechanics

This is probably the most basic of basic scanners, it will allow you to read and clear codes but wont provide any further diagnostics, you can scan the code which will usually start with a P0*** and then you can research the code via internet about the cause and possible solution. Most codes are very vague on very big systems. Also take with a grain of salt that the code found could may say one thing, but be caused by something else seemingly not related to the code. Its a starting point for diagnostics.

u/rinzlerslist · 1 pointr/Jeep

It's an OBDII port. You can plug one of these in to read Diagnostic Trouble Codes.

u/BrownNote · 1 pointr/Jeep

It can be really useful for any lights that come on. If you see yourself fiddling with your own cars in the future and have a bit of disposable income you could get a nice high quality one like this which will do everything you need, or you could get something as simple as this one to take care of most of your needs. Autel is a good brand, I also have a bluetooth one that connects to any app on your phone (or computer) which can also be convenient, and depending on the app can be useful giving you real-time data.

Note that for this issue specifically, you'd need the former one I linked as the airbag system (SRS) and ABS system run on a specialiszed part of the system and can't be read by normal code readers. So if you just figure you won't do much you could get the $15 reader for quick troubleshooting and take it to Autozone like you're doing for when big things come up.

u/FrontpageWatch · 1 pointr/longtail

>If your car is 1996 or newer and you get a check-engine light, don't pay a shop upwards of $100 just to run the code, there's better options.
>Option 1: Auto Parts Stores
>Most Auto parts stores have a code reader and will check your codes for you for free. Get the actual code that comes up on the screen and write it down. You can put this code into Google with the year/make/model of your vehicle to see common causes.
>Option 2: Buy a code reader
> You can buy a pretty simple code reader for under $20 online. You can also get an ELM 327 Bluetooth reader that will work with your smartphone. Torque Pro ($5 - Google Play Store) will read your codes, clear them, and even give you live engine data along with functioning as a dynomometer for 0-60 times etc.
>If you're not a mechanic, chances are you'll still need a trip to a repair facility to fix the problem, but this will give you a head start without paying to have the code read. A lot of times you'll even find a simple answer to the problem online by doing some research. For instance EVAP (Evaporative Emissions) codes are often times caused by a loose or poorly seated gas gap.
>Edit: Since most apparently did not read the whole thing:
>>If you're not a mechanic, chances are you'll still need a trip to a repair facility to fix the problem
>I'm not advocating DIY repair of your car, but knowing whether you have a misfire (big deal), or a small EVAP leak (not a big deal) can be very beneficial when you own a car on a budget.
>Edit 2: "Diagnose" should have said "read". Diagnosis is not the same as reading a code.

u/prothid · 1 pointr/DIY

Weird! AutoZone will read the codes for you for free, as someone else said. They'll probably reset it for you. I picked up a bunch of ODB II scanner tools off of Amazon for $20/each as stocking stuffers.

u/xyzzzzy · 1 pointr/funny

ODBII Scanner for the win. Best $17 I ever spent. This + Google means that if I have a loose gas cap or something stupid I can diagnose/fix it myself without going to the shop to get codes read.

FWIW often places like Autozone will read your codes for free, but then they want to sell you something to fix the problem.

u/hagdiggity · 1 pointr/mazda

I'm not familiar with wireless scanners but I would be curious if the added cost is worth the convenience. This one is around $100 and looks like it has a lot of features that you might not necessarily need/want if you're just looking for something that will read codes. Poking around on Amazon some more might find you a better price tool with less features.

If you don't mind the plug-in tools I would highly recommend - I bought one to troubleshoot a recurring CEL and was pretty happy with the price/ease of use. The Autel tool only reads and clears codes; you'll have to google the actual code to figure out what it is. Good luck!

u/melikeum · 1 pointr/BMW

I highly recommend grabbing a cheap OBD2 reader off amazon like this one. It can help you fix certain minor issues yourself or at least give you a heads up when you have to take it in for service.

u/SilverShrimp0 · 1 pointr/nashville

Well, the failed cat code means your oxygen sensors are probably working fine now. Here's what I would try. Get a ~$20 OBD2 code scanner from Amazon, and an ~$8 can of SeaFoam (from Wal-Mart, Kroger, or an auto parts store). Get your gas tank to about 3/4 full. Pour in the sea foam and use the scanner to clear the codes. Drive for awhile and use the scanner to check whether your sensors read as ready. I think you can have up to 2 sensors not ready with a vehicle model year prior to 2001. Once they're ready, if your check engine light is off, you'll be able to take it through inspection and pass.

u/barnyardman · 0 pointsr/Showerthoughts
u/calcium · -1 pointsr/financialindependence

Here's my suggestion if you want to pass emissions but don't want to repair your car. Go online and get yourself an ODB2 scanner for less than $20. Then when you pull up to the smog place next time, plug it in and clear all the codes on your car and then run the emissions test.

As long as the light doesn't come on during the test, you should be good to go and could pass your test. You can also go somewhere like AutoZone and have them check the code on your car for free to see what it is.