OBD2 Car ScannerTo read your car with the app you need a small ELM327 OBD2 adapter that plugs into the car's diagnostic port. They are cheap and easy to find online. Here is how to pick the right one.
Bluetooth, Bluetooth LE or Wi-Fi?
Classic Bluetooth adapters are the most common and work well with Android phones.
Bluetooth LE (4.0) adapters use less power and connect quickly.
Wi-Fi adapters create their own Wi-Fi network; your phone connects to it instead of your home Wi-Fi.
The app supports all three types.
Avoid the cheapest clones
Very cheap adapters sometimes use fake chips that drop the connection or don't support all cars. Choose one with good reviews and a real ELM327 v1.5 or v2.x chip.
Leaving it plugged in
Some adapters draw a small amount of power all the time. If you leave yours in the car, choose one with an auto-sleep mode or unplug it when you park for days.
Connecting for the first time
Plug the adapter into the OBD2 port, turn the ignition on, then open the app and tap Connect. For classic Bluetooth adapters, the pairing code is usually 1234 or 0000.
Read this code from your own car
Plug in a cheap ELM327 adapter and the app shows every fault code, what it means and how to fix it.