This device appears to be very similar to (and likely based on ) the ELM327 protocol converter, of which I own several. ELM Electronics developed the 327 to allow personal computers to connect to the communication buses on vehicles. The latest versions can talk to J1850, CAN & ISO9141 (the most common protocols in use on US road vehicles). It is a simple Microchip PIC processor which translates RS232 to the vehicle communiocation protocol. There are versions which use USB & now Bluetooth. They simply translate the USB or BT to RS232 which goes to the PIC which then translates it to the vehicle orotocol. You can search Ebay for ELM327 and find tons of them available for $10-$20.
Al US cars built since 1996 are required to support OBDII, and have a standard connector for accessing the engine & transmission controllers (and sometimes other) buses. It is always on the drivers side under the dash. An OBDII engine controller will support a standard set of diagnostic messages (and lots of other OEM specific messages.) This is what allows parts stores and independant mechanics to read the fault codes set inside the engine & transmission controllers to diagnose problems.
I bought several of these for my son & daughters and made them install the Torque app on their Android smart phones. That way when I get the "Dad, my check engine light came on" phone call I can talk them through reading the codes so I can tell if they just need to tighten the gas cap or if they have a more serious problem.
Hi Janine, for me being an engineer I like to understand how I'm influencing the car i drive and recently I had a case where my car had issues and the dealer said it didn't. Eventually I went to a different dealer that recognised there was an issue and fixed the car. For joe blo on the street I would have to agree with you, the last thing most drivers need is yet another distraction. I would want to see a ban on general use, or having a mode where while driving it only records data and has a blank screen (and no beeps) until you stop.
I purchased a PLX Devices KIWI Bluetooth OBD-2 scanner 2 years ago and have been using it on Android using Torque Pro ever since. There are any number of ELM32 based bluetooth adapters on the market today, most of them have the API available so that you can write your own apps. Existing apps provide the ability to show real time data as well as logged data.
The better apps integrate the GPS, compass, and inertial sensor data from the phone along with the OBD-2 data to povide comprehensive trip data.
Karen: Is it useful? I think so. I once test-drove a BMW 530i that had a little meter showing how much gas you were burning at any given moment. When it idled, it sat at about 18. When I accelerated from a dead stop, it dipped to about 9. And when I stepped on it to enter the freeway, it went down to about 6. I liked the car and it was a good price, but I couldn't stop thinking about how much gas it was burning. I ended up with an Acura.
It would be nice to have data like that so you could analyze your driving pattern. And it could prove invaluable should you ever have an accident. EG: If someone says you were going at least 50, you could calmly whip out your data and say, "Actually, I was going 24.2 mph just before impact."
David: Good post! It made me want one, too. But I do have questions: a) Droid? b) I'm not sure my car even has a plug for an onboard system. How would I know (or is it obvious in cars newer than my Acura?) Thanks.
Janine: From David's article, I believe the idea is to look at the data AFTER you drive so that you can review info like MPG, mileage and duration. Besides, there are plenty of distractions already when you're driving, not the least of which is an onboard navigation system. I don't have one, but I see people drifting out of lane all the time while checking to see where they are.
Thanks for all the questions and here are some answers.
Is it useful? after 4 days of use I think it is, it beeps annoyingly when I accelerate or brake too hard but I have turned those features off. It does show me speed, miles driven, fuel consumption and trip data so it could be very useful for people who need to track and claim mileage for work. If the car misbehaves it will show local mechanics and can send signals in a crash to designated numbers. So is it a revolutionary device? no its not but its a small step along the Internet of Things highway. I think car manufacturers are goign to see this and decide to offer it to customers themselves becuase there are HUGE marketing opportunities here for location based services and just think how much money can be made by selling gas, coffee, food etc...
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