1. In this episode, an auto self-destruct command is ordered, but nothing actually self-destructs as a result of that command.
From Quiz Name That Episode #19
Answer:
Basics, Part 1
When the Kazon have begun boarding Voyager, Janeway orders the computer to initiate the auto self-destruct sequence. However, because the previous strategically-planned Kazon attacks disabled the ship's processors, the computer is unable to comply, the Kazon soon taking control of the bridge following a brief phaser fight. In "Tinker, Tenor, Doctor, Spy", although the Doctor orders for the usage of a made-up destructive weapon called the 'photonic cannon' in both his daydream of fighting off the Borg and at the end of the episode when confronting the 'spy aliens' for real, he never gives an auto self-destruct command, and neither does Janeway nor Chakotay nor anybody else in this episode. In "Course: Oblivion", between the duplicate Janeway, the duplicate Kim (who had assumed the captain's role once the duplicate Janeway 'died') and the real Janeway at the very end of the episode, none of them gives an auto self-destruct command. One could say that the only thing that self-destructs on its own would be the duplicate Voyager and its duplicate crew altogether, which becomes nothing but a mass of deuterium floating in space at the episode's end. In "The Q And The Grey", between Janeway, Chakotay, both of the Q's popping up on Voyager and the Q in the Q Continuum (who are perceived as generals by the crew), none of them gives an auto self-destruct command in this episode either.