METHOD AND DEVICE FOR DETECTING CONDITION OF VEHICULAR LAMP

PROBLEM TO BE SOLVED: To improve detection accuracy when detecting disconnection (blowout) and recovery from disconnection of a turn signal lamp of a vehicle as much as possible. SOLUTION: A detection value of the lamp driving current in disconnection detecting timing when influence of unevenness of the electrifying current between lamps becomes sufficiently small near termination of each of lighting period, in which flashing is performed at normal speed in usual, is compared with a disconnection threshold value. Since the detection value of the lamp driving current in the disconnection detecting timing becomes smaller than the disconnection threshold value, disconnection of each of turn signal lamps 2a - 2c (3a - 3c) is accurately detected. When flashing speed becomes higher than the normal speed with detection of disconnection, a detection value of the lamp driving current in a recovery detecting timing set near a termination of each of the lighting period, in which flashing is performed at high speed, is compared with a recovery threshold value larger than the disconnection threshold value, and since the detection value of the lamp driving current in the recovery detecting timing becomes larger than the recovery threshold value, recovery from disconnection is accurately detected. COPYRIGHT: (C)2007,JPO&INPIT