Add One New Key/Keyless Transmitter

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2017 Honda Odyssey, 2016 Honda Odyssey, 2015 Honda Odyssey, 2014 Honda Odyssey, and 2013 Honda Odyssey. However, it is still accessible from the selected car via links, so may be relevant.

Have a registered key, a new immobilizer key, and the first password from the iN system.
Connect the HDS to the data link connector (DLC).
Turn the ignition switch to ON (II).
Select IMMOBI from the SYSTEM SELECTION MENU, then select IMMOBILIZER SETUP.
Select ADD AND DELETE KEYS, then ADD 1 KEY.
Do the registration according to the instructions on the HDS screen.
Check if the engine can be started by the newly registered key, and check that the door locks operate using the Immobilizer key transmitter.