Ob-la-di, Ob-la-da, OBD!

A little bit of OBDII history:  just what is an OBDII port and what does it do?

If your car was built after 1996 and has a gasoline engine, chances are high that it has an OBDII port. But what is its purpose, beside being what devices like Metromile’s Metronome are plugged into?

Metromile's Metronome plugs into your car's OBDII port and helps keep your car in tip top shape.

The OBD, or on-board diagnostics, port began as a way to measure a vehicle’s emissions. California, in particular, wanted a way to combat the growing issue of smog, so in 1966 they began to require emissions testing in all vehicles. This requirement gradually became adopted nationwide in 1968.

In 1988, the California Air Resources Board (CARB) passed a requirement that all vehicles sold in the state include on-board diagnostics. This first port would become known as the OBDI. If your car was made before 1996, you likely have the OBDI. Not sure if your car has an OBDI or OBDII? Here are three ways you can find out.

Flash forward almost a decade to 1996, when all new vehicles nationwide were required to include the OBDII. This next-generation of diagnostics had evolved from emissions testing to monitoring other performance-related aspects of the car, like the engine and chassis.

Here’s how the OBDII works:

  • Your car has a Powertrain Control Module (PCM) that constantly monitors the engine. If it detects a problem, like excessive oil consumption, your ‘Check Engine’ or service light will come on and remain on until the issue is resolved.

  • A repair technician can connect a scanner to the OBDII port, download your car’s data, confirm a diagnosis and start on the necessary repairs or resolution.

Check out this article to see when the OBDII was added to specific makes and models. For most vehicles, the port is located underneath the steering wheel.

The OBDII helps provide transparency into key operational features of your car so that you can make every effort to keep your vehicle in the best possible shape. Even with the amount of data provided, you should always make sure to stay up-to-date with your car’s maintenance schedule. Don’t delay changing your oil or overlook a Check Engine light that stays on.

If you have Metromile’s Metronome, then you already know how the OBDII can help you identify ways to keep your car at peak performance. Our Metromile app will decode those DTC’s (diagnostic trouble code) and even let you know the severity level. If you have any questions, you can click on the “Ask a Mechanic” button to ask our on-staff mechanic for advice. The app will pre-populate an email with those DTC’s so you won’t have to write them all down. You can also use our Sharing capability to send those DTC’s to your own mechanic directly (via Twitter, Facebook, SMS, and email).

Compatibility with OBDII devices can vary across manufacturers. We wish all car makes and models could magically be compatible with our Metronome! Until specs change, we won’t always be able to provide data for all car brands (check our site for any updates).

Wondering about security? The Metronome device pulls data in real-time from your car and transmits directly to Metromile’s secure data servers. The info is not sent directly to your mobile device. Rather, we make the data available in easy-to-interpret graphs and charts in 2 places:  our app (iOS & Android) and our web-based dashboard (log-in at metromile.com). In effect, data transfer is really only happening one way: from the Metronome device to Metromile secure servers. There is no danger of data going into the vehicle itself.

The OBDII is a great example of the evolution vehicles have gone through over the decades. What began as a way to test emissions has evolved into the portal for mechanics and drivers to obtain data about cars and fix potential problems. For Metromile, the OBDII is how we have unleashed the awesome amount of data to make driving less of a headache and enable drivers to make savvier decisions.

Want to read more? Check out this article’s sources: OBD II Background; Wikipedia; EPA.gov; CNET, “A Brief Intro to OBD-II technology”