2014 Nissan Altima Smart Key Programming with Autek ikey820 - took some trials but success
I have to admit this is not the best video but just use it as a guideline. I will make better videos.
Steps:
1. Use Menu #1 by vehicle, Key/Keyless Menu (not type 1, or type 2..failed to work)
2. Have both old key and new key for adding a spare.
3. Be careful, when it ask for you to press startup button at the menu instruction(don't press OK button until you are done with press/hold Nissan key to the start button), you probably have to press start button twice with the top of a key or your finger so the console will light up;otherwise it will not register), and immediately hold a new next startup button for 5 seconds and you should here 5 beeps to complete this step. If this fails, then go back and try this step again.
4. Press OK, it should say 'success', and ask you to program next key. Press ok to program the next key, and go thru the same steps above.
If a new key is not programmed, then it is probably due to failed pressing key to a start button steps. Try again, it should work, and be patient.
5. At the end, it will ask you to use key#1 to end the programming mode, just following similar instructions( ignition off, press start button/hold key next to it start button for 5 sec etc.)
Next similar cars should be easy. Make sure to only use (new or refurblished) OEM keys, not aftermarket.
Good luck.