Self-destruct

A self-destruct mechanism is an integrated device designed to render components, either in part or in full, from being used by unauthorized parties. Typically, such mechanisms can be set on timers, and utilize passwords or physical activation keys in order to either enable or disable the mechanism. In the case of disarming such mechanisms, there is typically a failsafe to prevent enemies from overriding the action, assuming that the mechanism has yet to reach a "point of no return" and thus can be safely disengaged.

Canon

In Galactica 1980's "The Night the Cylons Landed, Part I", the A-B Raider that crashes on Earth self-destructs at Andromus' order, tying the mechanism into the ship's scanners to self-destruct upon detection of humans, thus preventing not only the recovery of anything valuable but in the deaths of the transgressors. As it is set on a timer, Troy and Dillon manage to learn what they need and little else before escaping this fate.

In Re-imagined Series' "A Measure of Salvation", a basestar's self-destruct mechanism is engaged after a boarding party from Galactica recovers humanoid Cylons infected with lymphocytic encephalitis.

In the separate continuity

In the Original Series' tie-in Classic Battlestar Galactica Vol. 1 #5, Adama activates Galactica's destruct sequence from core command using a vocal command and passcode. After the Cylons are routed from core command by Captain Freg, Adama deactivates the system issuing a voice counter-order and separate passcode sequence.

Activation Code: "Set security protocol self-destruct—pass code, beta, Ila."
Deactivation Code: "Self-destruct cancel, beta-nine-Adama."

In the Re-imagined Series tie-in Battlestar Galactica: Origins #5, the Stealth Vipers are outfitted with self-destruct mechanisms to prevent these advance, new technologies from falling into enemy hands. Furthermore, a "nuke ship" has its self-destruct mechanism remotely activated by a Number Three before it can be deployed in Battlestar Galactica: Origins #3.