PURPOSE: To obtain the titled apparatus for preventing economically and effectively defectives without requiring an additional equipment such as setting means as in the prior art, by providing a timer, which is for the vulcanization of rubber items and which controls control valves for introducing or discharging a vulcanizing medium, with a mechanism for monitoring the operation of said valves.

CONSTITUTION: For example, a function output mechanism 26 including an electromagnetic valve, etc. outputs a function signal 27 by the output commad of a microcomputer 23 of a vulcanization sequence timer 1, and the function signal switches on or off the vulcanization internal pressure on/off control valves 28 so that various mediums responsible for the vulcanization internal pressure can be selectively introduced into or discharged from a tyre. At that time, by comparing the function signal from the function output mechanism with a signal from pressure switches 40 for detecting the pilot air pressure of each function by a comparing mechanism 41, the operation of the internal pressure on/off control valves is controlled.