When OBD2 was first required in 1996, it was viewed as a curse to enthusiasts and shadetree mechanics everywhere. Back in the day, you could invoke a complex ritual involving shorting out OBD port connector pins, reciting an incantation to Lucifer, counting how many times the light flashed, and consulting the Book of Armaments, chapter two, verses nine through twenty-one, only to discover you’re getting a “P0306 No. 6 Cylinder Misfire” from your four cylinder engine. But with the implementation of OBD2, there was no longer a way to get your car to tell you what’s wrong with it all by itself. This required a trip to the shop and an $80 bill for them to plug in their magic machine and say, “Uh, I dunno.”
Fortunately, things are different today. Many auto parts stores will plug in their scanner and get you the code for free. But even better, for a fraction of the price a shop used to charge you, you can buy your own wireless OBD2 scanner and see everything in an app on your phone or tablet. But diagnostics are just the tip of the iceberg. The added functionality is limited only by the creativity of the app designers, and DashCommand is one of the best I’ve seen for versatility far beyond simple troubleshooting.
(Full disclosure: I bought DashCommand last spring, just like any other customer, and have been using it ever since. Move along – there’s nothing to see here.)
At this point the car and the app are fully synched and all functions are available. Diagnostics are simple enough, displaying any trouble codes and descriptions for them that are stored in your car’s ECU. You can also clear the codes, which will shut the Check Engine light off. This is basic functionality that is common across all OBD2 scanners, but it’s delivered in a very clear and straightforward way in DashCommand.
The Gauges feature lets you create your own gauges for literally any parameter that OBD2 supports. For example, my BRZ doesn’t have an oil temperature gauge, and because I’ve read that these cars tend to run hot on track, I set up my phone with the largest oil temperature gauge I could for easy reference while lapping. Because of that, I discovered that my oil can get up to 250*F during a summer day, as opposed to around 200*F in regular street driving. Now I know that I would definitely benefit from an oil cooler on the track. I also set up small gauges to record max lateral Gs, max brake Gs, and my maximum speed and engine RPM, for review after each session. Now I know I can pull 1.1Gs on hot Michelin Pilot Super Sports, and over 2Gs under braking on track pads. Unfortunately oil pressure is not supported by the BRZ’s sensors, or I would have monitored both parameters simultaneously for piece of mind. That’s a shortcoming of my car, not of DashCommand. If the data was there, DashCommand could use it.
Here is where I insert a million disclaimers that the Performance section should not be used on a public road, that you should never exceed the speed limit, etc. With that out of the way, the Performance section lets you run 0-60 and 1/4 mile tests, using nothing but OBD2, the phone’s built-in accelerometers, and GPS data. Does anyone remember the old G-Tech Pro? Leave it in the toolbox – this does all the same stuff, and more. You get a real time horsepower calculation, plus you can save and share your runs all over the internet, because of course everyone is doing this far, far away from public roads where such aggressive driving is illegal.
There’s also a Race Track feature, and this is the only place where I feel DashCommand could offer a bit more. It automatically downloads a Google map of where you are, and superimposes a line of your route on top of it. The line is green where you accelerate, red where you brake, and in between where you’re in between. A small skidpad graph is displayed as well. It displays your speed, but calculated by GPS data rather than accurate OBD2 input. GPS resolution isn’t fine enough to analyze different lines through the same turn, and parameters like entry and exit speed aren’t recorded. There are apps designed specifically for track use that do a much better job of handling this data. I recently upgraded my iPhone and immediately downloaded Harry’s Lap Timer. I look forward to testing it the next time I go to the track, particularly for its excellent video features. Unfortunately, since I live in the frozen north, that probably won’t be until next year.
With a newer car like my BRZ, I don’t need a diagnostic app. If warning lights turn on, I take it to the dealer and get it fixed under warranty. But you can add multiple cars to DashCommand. I added my fiancee’s Ford Focus when the Check Engine light came on, and was able to diagnose and shut off the light. That, plus all of the extra features available in DashCommand, make it well worth adding to your phone or tablet’s bag of tricks. It won’t even claim you have a No. 6 Cylinder Misfire in your four cylinder engine.