Normal operation, if S2 is closed, Q1 is saturated, the oscillator stops oscillating, and this circuit is installed in the car. When the driver forgets to turn off the headlights. It can remind the driver to pay attention, at this time, the negative terminal of the car battery is grounded; B1 does not. The power of the oscillator is taken from the pilot panel indicator light. This is because it is considered that the indicator light always lights at the same time as the parking light or the front of the car, such as the ignition key turning on the circuit. If Q1 is saturated, Q2 and Q3 will not work. If it does not ignite, but the lights are still on, Q1 will be cut off and the oscillator
Liquid Crystal Display Module
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