Before Pairing your device make sure your Tecla Shield is in the desired mode. If you are not sure what mode you need check here: Tecla Shield modes.
If you are not sure how to change modes check here: Mode Change Instructions.
1. Go to Settings > Bluetooth.
2. With Bluetooth enabled, you should see the Tecla Shield DOS listed under Devices as TeclaShieldDOS-XXXX (where XXXX is a random sequence). Click on it. TeclaShieldDOS-XXXX should be under MY DEVICES and the status should change to Connected.