Pelican OBD

The basics

If you’re like most drivers, you learned about the existence of the OBD-II port only after something happened to your car and its check engine light turned on. A couple searches and videos later, and you’ve now found yourself in the footwell of your car, feeling around for a port that you didn’t know existed. That port is the OBD-II port, and it’s the gateway to talking your car.

What is OBD-II?

OBD stands for on-board diagnostics. It’s how your car keeps an eye on its own health. OBD-II is an automotive industry standard, required on every car sold in the US as part of emission regulation requirements since 1996 and in Europe since 2001, and also used on electric vehicles even though emissions requirements don’t really apply to them.

How it works

A modern car is a network of computers. The engine, the transmission, the brakes and the battery each have a control unit, and they talk to each other over a shared network called the CAN bus (Controller Area Network).

OBD-II requires that network to respond to a predetermined set of commands, and to respond with industry-defined parameters that help mechanics, emissions testers, and you evaluate the health of your car in a predictable way.

Codes and parameters

A car typically makes two kinds of information available over OBD-II:

1. Diagnostic trouble codes (DTCs) are what’s behind a check engine light. Each code points to an observed problem, which gives you and your mechanic a place to start.
2. Parameters (PIDs) are live readings a scanner can ask for at any moment, like speed, coolant temperature or an EV’s battery level.

Every car shares a standard set of parameters, and most makes add many more of their own, like a turbo’s boost or a battery’s cell temperatures. Pelican reads both, using the OBDb, the open database of vehicle signals. You can browse the parameters that work with different cars in the car catalog.

Getting started

1. Find your car’s OBD-II port

The port is inside the cabin, under the dashboard and below the steering wheel. It’s hard to find by feel from the driver’s seat, so look for it with a flashlight. Check that your car has one before you buy a scanner. Most cars do have one, but the position of the port varies by make, model, and year.

2. Buy a scanner

Pelican works with three kinds of scanner:

• Bluetooth Low Energy (BTLE) scanners connect on their own whenever they have power and your phone is nearby. They’re the best choice, and they work well with wireless CarPlay.
• Wi-Fi scanners need you to join their network each time, and can’t be used at the same time as wireless CarPlay.
• Classic Bluetooth scanners can auto-connect, but require you to leave the scanner powered on at all times for that auto-connect behavior to work. These scanners often have a low power mode that they can settle into when you’re not driving.

Avoid BLCKTEC scanners, including the 410 and 430, and OBDeleven scanners. They use their own protocols, which no general-purpose scanning app, including Pelican, can talk to.

3. Connect Pelican to your scanner

In Pelican, open Settings > OBD scanning > Your scanners.

Add BTLE scanners directly from Pelican, not in the iOS Bluetooth settings. Classic Bluetooth scanners, on the other hand, require you to pair it in the iOS Settings app first, and only then will it appear in Pelican. To connect to Wi-Fi scanners, join their network first.

Turn on Auto-connect known scanners and Pelican will connect automatically to your scanner whenever the app opens or a trip starts.

Daily scanning

Most scanners let any nearby device connect to them while they have power, so a scanner left plugged in can be a security risk for your car. Unplug it when you’re not using it, or use an OBD extension cable with a power switch, so you can turn it off without reaching under the dashboard.

Scanning is free in sessions of five minutes. ScanPlan or Pelican+ removes the limit, and a ScanPass gives unlimited scanning for a day or a week, with no membership needed. Compare them on Pelican memberships.