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Help Me, Help You: Utilizing OBD-II Scanner Technology

You’re driving along the interstate or in bumper-to-bumper traffic. All of a sudden, your car emits an alarming noise and a little orange or yellow silhouette of a submarine pops up in the gauge cluster. Maybe the glowing icon appears and goes away and you never give it a second thought. Perhaps it comes on and then stays illuminated, even after you stop and restart your car. Or maybe it starts flashing. Spoiler alert: If the light is flashing you will want to pull over and stop the engine as soon as it is safely possible, your beloved transportation is warning you that enough is enough.

Of course that little light has nothing to do with a submersible watercraft, what you are looking at is a tiny visual representation of an engine. Not that it matters, but the silhouette resembles an engine block and transmission with an air cleaner on top and a radiator fan to the left. The illumination of the check engine light (CEL) or malfunction indicator light (MIL) is your vehicle’s way of telling you that something is wrong.

2016 Hyundai Genesis (CARFAX, Inc.)
2016 Hyundai Genesis (CARFAX, Inc.)

Since 1996, the check engine light represents one or more of an industry-standardized list of diagnostic codes that can be used to help diagnose the problem. Before 1996, each manufacturer had a specific set of parameters and messages that the light indicated. The present standardization, known as On-Board Diagnostics II (OBD-II) also resulted in a universal connector that is typically found just underneath the vehicle’s steering column. By using the appropriate interface, a computer can be attached to the OBD-II port and the diagnostic messages can be read and analyzed, aiding in the vehicle’s repair and return to service.

When the interface first became available, the technology needed to read a vehicle’s OBD-II codes was often bulky and too cost prohibitive for consumers to take full advantage of the built in diagnostic system. Fortunately, over the past decade the rapid advancement in handheld electronics means that code readers are readily available to consumers. Many auto parts stores also offer code scanning services for free to customers.

OBD-II Scan Tool (CARFAX, Inc.)
OBD-II Scan Tool (CARFAX, Inc.)

The majority of home mechanics may already have a trusty OBD-II scan tool sitting on a shelf or in a vehicle glove box, but for the rest of us it is important to know exactly which kind of scan tool to purchase. Just as important is whether or not we need to purchase one at all. While this article is in no way meant to be an exhaustive discussion of today’s readily available OBD-II readers, my hope is to give you some basic information that will help you decide if you should invest in a scanner, as well as what type of scanner will best fit your needs.

It’s All About the Features

Even a quick online search will reveal hundreds of OBD-II scan tools that are available for anywhere from $50 to $3,000. The variety of options is a boon for consumers, but without a little key information you could easily purchase a scanner that only reads a small amount of your vehicle’s available data. With up to five different communication systems used in OBD-II equipped vehicles, it is important to contact your vehicle’s manufacturer or consult another reliable source to discover which OBD-II systems your automobile supports. Once you know what information is available, you will want to purchase a scan tool that will allow you to download the information you need.

Of course very few people keep the same car forever, and even if you do it is wise to buy a tool that can be used on more than one vehicle and easily upgraded in the future. If you find that your current ride only needs an inexpensive basic scan tool, you might want to buy a relatively cheap unit and retire the scanner with the vehicle when you sell it or trade it in. On the other hand, if you are making a sizeable purchase to cover all of your vehicle’s systems, the ability to upgrade will enhance the scan tool’s value well into the future.

OBD-II Scan Tool (CARFAX, Inc.)
OBD-II Scan Tool (CARFAX, Inc.)

I’m not encouraging you to open a repair shop based out of your garage (the permits and zoning alone would make your life fairly difficult). However, I can’t count how many times I have lent out one of my scan tools or helped a neighbor quickly diagnose a problem that triggered the check engine light.

Fairly recently, I was able to use my scanner to help patch up a car that belongs to my next-door neighbor’s kid. Right around the holiday break the car had arrived limping home from college with an illuminated check engine light. Diagnosis only took a few minutes. Turns out the road-worn 1999 Mitsubishi Eclipse was throwing a P0340 code and simply needed a $50 camshaft position sensor to get it back to school running better than it had in a while.

While I have found the Internet (particularly Google searches) with the presented code or codes alongside the vehicle’s year, make, and model to be invaluable in diagnosing repairs, many of the better scan tools will provide the trouble code and a description of the code right on the scan tool’s screen. Some will even use vehicle-specific information to report which parts need to be replaced, adjusted or corrected to remedy the problem. While I think you can live without the extra information if you are handy searching online, having it all in one place is efficient and worth considering when making a purchase.

Wired or Wireless OBD-II Scanners?

BlueDriver Wireless OBD-II Scanner(CARFAX, Inc.)
Lemur BlueDriver OBD-II Scanner (CARFAX, Inc.)

The traditional scan tool uses an interface that plugs into the OBD-II J1962 port located close to the vehicle’s steering column. A wire is then plugged directly into a computer or terminates in a dedicated handheld tool with buttons and a display. Many automotive shops and dealers will have large, computer-based machines that allow deep two-way communication between the scan tool and the vehicle. While the dealer’s pricey scanner is completely unnecessary for the home mechanic, the smaller handheld units are the most popular and very useful for many driveway wrenchers.

Recently, a new wireless Bluetooth OBD-II scan tool that works with a smartphone or tablet has been introduced to the market. It changes the OBD-II rules, making complex code scanning and real-time vehicle information readily available even for those on a shoe string budget. The small Bluetooth-enabled harness plugs into OBD-II port and syncs up to your smartphone or tablet in a matter of seconds, allowing for easy vehicle scanning, an assessment of systems that are currently running and much more. The system also stores codes on your device’s internal memory and keeps extensive logs for future reference.

Lemur BlueDriver Smartphone App (CARFAX, Inc.)
Lemur BlueDriver Smartphone App (CARFAX, Inc.)

I’ve been able to spend about a year with a Bluetooth scan tool (in my case, a Lemur BlueDriver) and I can’t recommend it enough. The model I purchased is a relatively inexpensive wireless module that works with Android and Apple devices, and the smartphone application is constantly being updated. Similar to many comparably priced standalone scanners, the BlueDriver lets you read and clear diagnostic trouble codes, but that is only the beginning. It also generates repair reports that contain the code’s definition, possible causes and the top or frequently reported fixes. This tool can also let you know if your car is ready to pass a smog test, if your state requires one. While most home techs won’t require Mode 6 data, it is available through the app, and a live data view turns your smartphone into the extra gauges that you don’t already have on your dashboard. I particularly appreciate being able to see real-time data like the vehicle’s fuel rail pressure, which is information I’d never know without the interface.

Your Car Might Already Have an OBD-II Scanner

2016 Hyundai Genesis (CARFAX, Inc.)
2016 Hyundai Genesis (CARFAX, Inc.)

I recently reviewed a Hyundai Genesis sedan and was intrigued by the “System Check” visual that pops up in the center of the gauge cluster at start up. A little investigation revealed that along with checking the sedan’s tire pressure and fluid levels, Hyundai’s Blue Link system was also checking to see if the Genesis was throwing any OBD-II monitored trouble codes. If enabled, the system can send the information to a local dealer automatically.

Once a month, Hyundai automatically gathers and uses the information to compile and email a monthly vehicle health report that verifies the car’s mechanical condition. It also advises on upcoming maintenance and provides helpful ownership tips. Considering the 2016 Genesis is under warranty and the system is completely automated, I must say it is quite impressive (I can’t wait until the car will drive itself to the repair shop and then back home again). With the driver assistance technology that is already available in a car like the Genesis, I can’t help but imagine that the reality of cars taking themselves in to get repaired happens during my lifetime.

2016 Hyundai Genesis (CARFAX, Inc.)
2016 Hyundai Genesis (CARFAX, Inc.)

If you want to check the vehicle diagnostics manually, the 2016 Genesis simply requires you to push the Blue Link button and follow the screen prompts. It only took a few seconds to see that my review vehicle was in good running order, and the added convenience provided by the built-in system seems like something that all automakers might want to investigate for the future.

Scan Tool Empowerment

Whether you buy a scan tool, or simply visit a local auto parts store and use theirs for free, an OBD-II scanner is a great way to diagnose many vehicle repairs inexpensively and easily. More importantly, vehicles built since 1996 already have the interface, so why not take advantage of the capabilities? Just remember to do some research before you buy and seek wise counsel before purchasing parts based on a trouble code. Even if you never plan to lift a wrench, owning an OBD-II scan tool empowers you to be a part of repair decisions by arming you with vital and self-confirmed information.

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