All your problems can be solved by NOT doing one thing.
This article covers pairing an OBD car diagnostic tool with an Android phone **but** the principle is the same for all Bluetooth pairing devices.
In summary, the key is to pair your Bluetooth device to your phone use the phone’s settings menu and only when the device is paired should you open your app and attempt to connect to your Bluetooth device.
Full Version & Step by Step Guide – Bluetooth Pairing Android
Below I’ll walk you through each step of the pairing process.
The one thing NOT to do is trying to pair to the dongle through the Android App.
There are exceptions to the rule but generally trying to connect to the dongle through your App is not going to work.
For one simple reason.
You must do the Bluetooth pairing between your OBD2 Bluetooth device and your phone BEFORE you open the Android app.
If your OBD2 dongle is not connected/paired with your phone your App will probably not “see” it and if it does “see” it, it will probably not connect to it.
Your must pair the Bluetooth device with your android device first.
To connect your OBD2 Bluetooth device to your phone.
Insert dongle into the OBD2 socket on the car.
Turn on the ignition, not the engine, just the ignition
OBD2 device will have power
Open your Android phone.
Go to the settings menu (of the phone)
Go to Bluetooth
Switch on Bluetooth if it is not on already
Find new devices
If your Android phone does not see the OBD2 device, switch off Bluetooth on the phone and switch it back on.
Still no joy?
Unplug the OBD device and reconnect it to the car.
Repeat until your phone sees the device.
Pair your phone to the newly found OBD2 device.
Password is usually 1234
When its paired you are good to go
Open the Android App of your choice.
Follow the procedure to allow it to use the paired OBD2 dongle.
And that is it.
Like I said at the start. The biggest problems people have (in my experience) is trying to connect with the dongle through the downloaded App.
What can add to people’s confusion is the fact the OBD2 dongle may even show up in the App itself.
But the App will not be able to connect to the device until it has been paired.
If it has not been paired it will not connect.
Hopefully this article will help you connect your Android device to your OBD2 Bluetooth device!