To reduce the number of terminal of a control circuit.
One side terminals of light-emitting sources L1-L3 are grounded via switches SW1-SW3 and the other side terminal are joined to a power source 16 via a terminal U1 of a control circuit 15, field effect transistors TF1, TF2, and a terminal U4 in a power supply circuit 31. A control circuit 25 turns on or off the field effect transistors at a predetermined cycle when the switches SW2, SW3 are turned on, and turns them on when the switch SW1 is turned on, and turns them off when the switches SW1, SW2, SW3 are turned off. A signal supply circuit 32 supplies an inspection signal to the light-emitting sources L1-L3 from the terminal U1 via a diode D1 of a judgment circuit 33 while the field effect transistors TF1, TF2 are off. When the inspection signal is supplied to the light-emitting sources L1-L3, the switches SW2, SW3 are judged to be turned on and when the inspection signal is not supplied to the light- emitting sources L1-L3, the switches SW2, SW3 are judged to be turned off.
MATSUMOTO TOSHIHIRO
ASADA HIDEKI
TOYOTA MOTOR CORP
| JP62502481Y | ||||
| JPS5921766A | 1984-02-03 |