There was a time when you could open the bonnet of a car, look beneath it and see the engine in all its mechanical glory. If something went wrong, you'd more than likely be able to see something, or hear something - or in some alarming cases, smell something - that would help you diagnose the fault.
These days, cars are more like computers and less like cars. There's a load of computer stuff involved, and usually a liberal lump of plastic to keep inexperienced hands away from the business part of the car. Engines haven't changed much in their essence, they work the same way as ever, but now there's a clever computer that manages the whole thing.
So when something goes wrong, you need to talk to the computer, not the engine. That's where OBDLink MX comes in. It's a Bluetooth dongle that fits into the diagnostic port of your car, talks to it, and can tell you what's going on.
But there's a lot more to it than just fault finding. Apps for phones mean you can see a load of cool information while you're driving, or even monitor your performance when you take the car on to a racetrack. Of course, everyone will have different needs, but we think most people will get a kick out of being able to see what's going on with their car.
The OBDLink MX is small, so you should be able to get it in your car's diagnostic port with relative ease. Once it's in you have to turn the ignition on, but you don't have to start the engine. From there, it's a simple matter of pressing the Bluetooth pairing button on the bottom left of the dongle, and then finding the device with either your laptop or phone.
There are lights on the front which tell you about the status of the dongle. It will show you if it's paired, or waiting to pair, as well as when there's power going to it. It's really easy to use, and we had no problems at all using it. It's claimed to be a very low power drain too, meaning you can leave it connected without worrying it's going to sip all your power away.
Does my car have an OBD port?
Yes, it almost certainly does. All EU vehicles running on petrol have legally had to have an OBD port since 2001, and it was mandatory on diesel cars from 2004. So if your car is less than 10 years old, it will have one of these ports and you can use this tool to access it.
Where it is varies wildly from vehicle to vehicle. In our Audi, it lives under the dash on the driver's side near the accelerator. In a Skoda from a few years back it's a bit higher up. There are websites geared up to help you find your port if you're having problems.
And, of course, different cars will have different information that's sent to the port. Features available will depend on what sensors your car has. It's fair to guess that RPM and speed information will be quite universal. Other stuff like turbo pressure and the like will depend on your car.
The good thing about OBD is that it's a standard which all car companies adhere to. This means that there's a really good selection of apps in the various app stores that can connect to the OBDLink MX and read data from it. This means you can pick an app that shows you the information you're interested in, and avoid the stuff you aren't. Some are more aimed at diagnostics, others are about seeing engine output graphically.
First though, there is a Windows application included with a serial number in the pack. Called OBDLink MX, it allows any Windows laptop with Bluetooth to connect to the dongle and read the information in the same way you would on a smartphone. The only difference is, the information is more detailed on the laptop, and less geared towards a pretty design, because it's not really supposed to be used while you're driving but more as a diagnostic tool.
For Android, there are lots of apps that can talk to OBD interfaces. The official app is called OBDLink and it's good to use. It's simple, but gives you access to all the funky information you want, while at the same time letting you see the error codes that might have come up.
Another app called DashCommand offers a lot more, but requires you to pay $9.99 (£6.60) for it. Not an excessive amount, and you do get a nicely laid-out interface that has some well-designed graphical meters for when you're driving. It also does well in the diagnostics stakes giving, offering lots of information about the car and allowing access to tools that use the sensors in your phone, as well as those in the car. This gives you charts that show your g-force and an inclinometer - which might be handy for off road driving. DashCommand was the only app we could find that made it easy to see the turbo pressure too, which scored it points with us.
There are dozens of other apps, for pretty much any device you can lay your hands on. We've concentrated here on those which work on Android, but there are plenty for iOS too, although we noticed that on that platform DashCommand is a staggering £28.
We tested the OBDLink MX with our Audi A3 TDI and an older Skoda, it worked flawlessly on both. On the Skoda, an ongoing problem required a reset of the errors, which was easy to do. Watch out for this though, you might get into an argument when you take the car in for a service next. Also, resetting things can cause your car to temporarily run badly, although the ECU should sort that out reasonably quickly.
There was nothing wrong with the Audi, so most of our time here was spent playing about with cool dials and stuff. It's nice to have access to a little more information than the standard dash gives you. It might not be essential, but if you understand cars it might give you some insight into what yours is up to while you're driving. You can log too, so you don't have to scrutinise data as you drive.
If you like track driving, there are some nice tools for this too. One app even lets you record video from your phone's camera, while overlaying information about what's happening. It's a clever idea, we rather like it.
Ultimately, there's not a lot of reasons for most people to buy the OBDLink MX, but if you're a car nut or someone who loves information, it will be something of a dream come true. In the time we've had it, it's proved to be useful for seeing what errors a car is throwing up, and it gives you an easy cheat when it comes to talking to a mechanic.
There are potentially lots of other things you can do with the OBDLink too, like tweaking your engine, but this is something that goes beyond the scope of both this review, and our engine tweaking knowledge.
It's almost a no-brainer for the petrolhead, and the Bluetooth nature of the OBDLink MX means that it's a lot more convenient than a wired system, and a lot more compatible too. It is quite expensive, but as you'll be able to carry on using it with every car you own from now on, it's a manageable cost.
The OBDLink MX we used in this review was kindly supplied to us by ESP Automotive.