0 Car Headlight with Delay Circuit

What this circuit does is when you push the push-button PB1, it will make your headlight turns on for several seconds or minutes then it will turn off. The idea of this is when you push PB1, the capacitor C1 will charge and transistors Q1 and Q2 are on. During this instant, the bulb is on. When PB1 is open, the charge will drain to the resistors R1 and R3 until the capacitor voltage drops to a certain voltage that will turn off the transistor Q1 (bulb is off). Increasing the value of capacitance increases the duration of the delay. The circuit is very similar to Delay Switch using Transistor and Delay Off Circuit.
Pinout of Q2 (BC327, 9012)
Pinout of Q1 (2N2222, 9013)
Part List:
R1 - 3.9 kilo ohms 1/4W
R2 - 1.2 kilo ohms 1/4W
R3 - 1.2 kilo ohms 1/4W
C1 - 47uF electrolytic capacitor rated 16V
D1 - 1N4001 or similar diode
Q1 - 2N2222, 9013 or similar NPN transistor
Q2 - BC327, 9012 or similar PNP transistor
RELAY - 12V relay with internal resistance 100 to 500 ohms
BULB - 12V  bulb
PB1 - any Push-button


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