MONITORING DEVICE FOR VEHICLE STATE

PROBLEM TO BE SOLVED: To provide a monitoring device for a vehicle state easily assembled as an option to the vehicle and capable of determining a half-open door state with high accuracy, determining the open state of a window without any error and warning a closing failure of the door and window. SOLUTION: Variation of air inside a cabin is detected by a sound pressure sensor 2, subjected to waveform processing by a discrimination decision circuit 3 and incorporated into an input port of a control part 1. The control part determines by collation with each detection signal indicating the situation of the vehicle, of a courtesy switch 4 or the like for detecting the open/closed state of the door, and operates an alarm 6. When the courtesy switch does not show the closed state of the door within a fixed time after the sound pressure sensor shows a change from an open state to a closed state of the door after the courtesy switch shows the open state of the door, the door can be determined to be in the half open state. When the sound pressure sensor does not show a change from the open state to the closed state of the door within a fixed time before and after the courtesy switch changes from the open state to the closed state of the door, it can be determined as the failure to close the window. COPYRIGHT: (C)2006,JPO&NCIPI