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CarMD Review – Automotive Vehicle Diagnostic Scan Tool to Avoid Scams



You take your car in for routine maintenance and the mechanic comes back saying that the car has about five different issues you weren’t expecting. You want to believe that they are telling you the truth, but mechanics in general don’t have good reputations so it’s hard to take them at their word. Does this sound familiar?

If you’re like me and don’t know much about cars, chances are that you’ve run into this situation more than once. By now you probably dread taking your car to the mechanic.

This is where a product like CarMD comes into play. The folks at CarMD developed the product to put more knowledge and power in the hands of the car owner, rather than the mechanic (where you can easily fall prey to a scam).

carmd reportJust like so many other things in life these days, all of the electrical components in your vehicle run from a computer chip. Even your engine sends codes to this chip when something is wrong. Before CarMD, the only way to read these codes was to bring it into the mechanic or dealer and use their equipment.

If you’ve ever paid for a “diagnostic fee” from the mechanic, you know that the price for the test alone can be pretty steep. And they’re not even fixing anything yet. You’re paying them to hook up a machine that pulls the codes from your engine to figure out what the problem is.

CarMD’s device allows you diagnose your car without taking it to the mechanic, saving you time and money. I was fortunate enough to receive the CarMD and test it on my cars. Here’s what I found out about it.

How CarMD Works

CarMD is a pretty straight forward product. For the total cost of $119, you receive the diagnostic tool as well as the appropriate software. Below is a step by step breakdown of how the process works.

  1. Find your CarMD connection. This could be the hardest part of using the CarMD product, if not for the helpful guide on their website. Instead of trying to find the connection myself, I just went to their website to input my make and model, and CarMD popped up a nice picture and description of where the connection should be for both of my cars. You can even run the search before creating an account. Be sure that when you go out to your car, you write down the VIN number. You’ll need to type it in when you sign up for a new account on the CarMD website. The VIN number can be found in the corner of the dash on the driver’s side, on your car insurance card, or on your registration paperwork.
  2. Connect your CarMD and turn the ignition of your car “on.” Don’t turn on the car’s engine, just turn the key to the “on” position, like you would if you wanted to put the auto windows down. You have to do this within 10 seconds of hooking up the CarMD device, or you’ll get an error message. If you get a “good” connection, it’ll beep twice.
  3. Wait for the beep. Wait until the CarMD beeps 4 times. This means that it has successfully retrieved your car’s diagnostic information. Sometimes it takes a while for it to beep, so just be patient.
  4. Load the CarMD software and sign up at If you’re good with computers and installing software, then this step should be a breeze. The nice thing is that it’ll work on both Windows-based PCs and Apple Macintosh computers. Once the software is loaded up, plug in the CarMD via USB port, sign up for a new account on, and view your test results.

I followed these steps when using the product on each of my cars. To help further inform you, I videotaped my experience.

My Experience with CarMD

Watch this short video to see how I actually used the CarMD device.

1. My 2006 Hyundai Sonata

I connected the CarMD to the Sonata after I located the hook up under the steering wheel. Luckily, I got a GREEN light. When using the CarMD, a GREEN light is your best friend because it indicates that no problems were detected. That doesn’t necessarily mean your car is perfect, but it does mean that the computer in your car isn’t trying to tell you anything.

2. My 2003 Nissan Xterra

This car was a different story. The CarMD pulled a P0328 code from its computer. I got the report from the CarMD website, and it explained that this code meant that the engine’s knock sensor is going to go bad.

I’m not a car person, and I had no idea what a knock sensor was. Even after Googling it, I’m still a little confused about what it does. I think it senses if the engine is literally “knocking” or, in other words, the engine is not secure to the engine block. Car people, please correct me if I’m wrong.

Anyway, after reading a lot of forums online, it looks like the jury is kind of out as to whether this is a serious problem or not. From what I gather, it can cause a decrease in engine performance, fuel economy, and acceleration. That actually makes sense, because I’ve always noticed my Xterra has really bad acceleration and less than desirable fuel economy. What do you think? Should I replace it? Will it screw up my engine over the long term?

As you can see, I came away from the experience with more questions than answers. That being said, I’m glad I had enough information to research the problem on my own before paying a mechanic for the diagnosis. So, what was my take-away from using the product?

Pros of CarMD

I found that CarMD had several things going for it:

  1. Simple to Use. If you’re not completely helpless on a computer and if you can find the 16 pin input to plug in the CarMD on your car, the whole process is fairly simple.
  2. Informative. It does give you useful information such as the engine diagnostic codes, estimated repair costs, and manufacturer recalls.
  3. Helpful Website. The feature on their website that helps you find the connection on your particular make and model is really handy.
  4. Convenient Size. The CarMD device is very light and portable. It’s small enough to keep in your glove compartment.
  5. Compatibility. It’s compatible with PCs and Macs. I had no problem installing the software on my Mac and it read the data quickly when I registered on the site.

Cons of CarMD

There are a few drawbacks that should be considered before you purchase CarMD:

  • One Car at a Time. I had to grab the data from each car and load it onto the website separately. This was a bit tedious and time-consuming. I could not figure out how to upload both at the same time.
  • Technical Descriptions. The descriptions given of the engine codes were not the most intuitive for the laymen. I had to do a lot of research online to figure out what a knock sensor is and if I should be concerned about it.
  • Dark Screen. The screen doesn’t light up. If you needed to check it at night, you’d have a hard time reading it. For $119, you’d think they could put a backlit screen in there.

In addition to these issues, I think that some of the codes pulled might not be necessary to take action on. People might spend a lot of money without truly needing to replace whatever the engine codes recommend. In my case, it seems like a judgment call, and I’m not qualified enough to make that on my own. I’ll probably end up consulting a few car people who I trust to find out if I should replace the knock sensor right away, or wait a little bit.

Final Word

Obviously, I wasn’t happy to see that my “knock sensor” is bad in my Nissan Xterra, but at least now I am aware that there’s a potential issue.

Admittedly, the $119 price tag might deter some folks from rushing out to buy the CarMD, but overall, it can definitely save some time and money by empowering consumers to know about potential issues before they become bigger concerns. It would be a great gift to give someone, and I would be really happy to receive it as a gift myself.

As far as this product paying for itself, ease of use, and the amount of information and tools on the CarMD website, I give it an “A.” They made the process very simple and I had no problems from start to finish. CarMD is a quality product, and it’s a product you should consider buying if you have an older car (but no older than 1996), and you’d like to get a leg up on potential repair issues without relying on the mechanic to give you an honest opinion.

Have you, or someone you know, used CarMD? Was it worth the price? Please share your experiences in the comments below.

Erik Folgate
Erik and his wife, Lindzee, live in Orlando, Florida with a baby boy on the way. Erik works as an account manager for a marketing company, and considers counseling friends, family and the readers of Money Crashers his personal ministry to others. Erik became passionate about personal finance and helping others make wise financial decisions after racking up over $20k in credit card and student loan debt within the first two years of college.

Comments Disclosure: The below responses are not provided or commissioned by the bank advertiser. Responses have not been reviewed, approved or otherwise endorsed by the bank advertiser. It is not the bank advertiser's responsibility to ensure all posts and/or questions are answered.

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