[1]"Alright... testing of the Code Green: Casshern Restraining Bolt one-point-oh... take one!" "I swear to god, if I get killed, my wife's suing the captain! In a Brittanian court!" "And... go!"
Casshern was standing at the far end of the room, looking somewhat nervous. He had his helmet on, when the main, clad in a full suit of armor and a bulkhead in between them ready to snap closed, was already shaking. "I said, and, go!" "FINE! Damn, I'm sorry, I don't wanna have my guts ripped out."
The main raised his beam rifle, pointing it at Casshern. Immediately, Casshern's berserk mode sensed the threat, and his facemask closed, his eyes lighting up.

"TURN IT ON!" Casshern started coming towards him, slowly, threateningly. "TURN IT ON!" "I'M TRYING!" Casshern started walking faster, just slightly below the speed of a normal human running. "Turn it on or shut the bulkhead, come on!" "There!" And finally, after the eighth time of pressing the button, Casshern suddenly dropped to his knees, his hands on his head, as if he suddenly had a
massive migraine. After an agonizing thirty seconds, Casshern fell to the ground, passed out, his eyes wide open. Somehow, they had shut him down.
[2]
When the restraining bolt was deactivated, Casshern can be found in the infirmary, his hands palms pressed into his closed eyes. "They didn't have to make it so painful," he complains. And sure enough, on the back of the base of his neck, well-hidden by his hair and the high collar of his combat suit, was a small, square protrusion of something that appeared to be jammed into his spine. A restraining bolt meant to temporarily disrupt his AI with looping, hanging codes injected into his most basic runtimes, causing his OS to crash. This would happen when his berserk mode activated at an inconvenient time, and would be handled only by Ayame, who would be alerted by Dan the moment Casshern went psycho.
However, Casshern had been informed that his unique healing abilities and rapidly evolving and highly-advanced nature of his AI made it unstable at best and potentially unreliable at worst. Meaning, Casshern was still going to have to undergo routine software maintenance to ensure the restraining bolt still worked. And when that happens, they're praying that they're able to shut Casshern down before he caused any serious damage. Until then, they were still working on contingency plans for if his berserk mode activated while on the ship, he was still under 24-hour surveillance by Dan, and it was still mandatory that nobody do anything that could be construed as threatening directed at Casshern.
When someone would pass by his open door in the infirmary, Casshern would try to get their attention. "Could you... get one of the doctors for me? Or maybe Ayame?" he'd politely ask. "I'm... kind of curious as to what happened to that blood sample I gave. And I'm still having those nightmares every time I shut down."