Space-time locator

The space-time locator was a mechanism used in TARDISes to plot courses through space and time. It could be damaged by vibration caused by a TARDIS' dematerialisation being too abrupt.

The space-time locator in the Doctor's TARDIS was damaged when the First Doctor departed from Skaro. (PROSE: Peril in Mechanistria) It was damaged again when the Doctor and his companions departed from Corbo. (PROSE: The Playthings of Fo)