Patent ID: 7136780

Claim:
An apparatus for diagnosing a timer circuit that automatically activates a device, the device being activated or deactivated when a switch is operated, the timer circuit measuring the time elapsed from when the switch is operated to deactivate the device, and the timer circuit automatically activating the device temporarily when the elapsed time measurement exceeds a predetermined time, the apparatus comprising: a storage unit for storing a history of execution of automatic activation of the device by the timer circuit; and a determination unit which receives the stored history of execution and determines that an abnormality relating to the execution of automatic activation has occurred in the timer circuit if the elapsed time measurement and the history stored by the storage unit do not correspond with each other when the switch is operated to activate the device, wherein the determination unit determines that an abnormality relating to the execution of automatic activation has occurred in the timer circuit if the elapsed time measurement is shorter than the predetermined time and the storage unit stores the history of execution of automatic activation of the device by the timer circuit when the switch is operated to activate the device, and wherein the determination unit determines that an abnormality relating to the execution of automatic activation has not occurred in the timer circuit if the elapsed time measurement is shorter than the predetermined time and the storage unit does not store the history of execution of automatic activation of the device by the timer circuit when the switch is operated to activate the device.