Fail-safe detonation system

Fail-Safe Detonation is a term that is used to explain the Self Destruct system of a WIA or KIA Spartan-II's MJOLNIR Powered Assault Armor. Once a Spartan-II is killed or wounded fatally, the protocol will have to be enacted by either themselves or a nearby Spartan. This is done to avoid capture of the suit and/or the wearer for identification or technological study. It is unknown if the Mk. VI has this capability, since the Mk. V is said to have one.

Effectiveness
The tiny access panel at the back of the suit is opened to activate the protocol, it is activated by typing several digits only Spartans know. Once activated, a fifteen-second countdown timer starts. Once it hits zero, the the suit's fusion reactor overloads and burns everything in its path in a ten-meter radius with a follow-up explosion to finish anything alive.

Trivia

 * The Master Chief is the only known Spartan to activate the Fail-Safe Detonation (on Grace-093's suit after she was killed by a Brute in the Covenant city of Unyielding Hierophant).