This is a simple circuit that can be used as a sequential signal light in automobiles as a signal. The circuit is based on two ICs. A TS555 Timer IC and a CD4017 decade counter IC. The IC1 is configured as an Astable multi-vibrator mode. When triggered, the outputs of the IC2 goes high and low (on pins 3, 2, 4 and 7)in sequence and the speed of this sequencing will be depend on the triggering frequency. The transistors Q1 to Q4 drives the corresponding LEDs. The switch S1 can be used to select the direction of turning and the LEDs arranged at the corresponding side of the vehicle will start sequencing.
IC1 = 555 Time, IC2 = CD4017
VR1 = 500K, R2 = 47K, R3 = R4 = 470R(ohm), R5 - R8 = 10K
C1 = 1uf 63v, C2 = 220uf 25v
S1 = SPDT switch, S2 = ON/OFF switch
Transistor Q1 – Q4 = BC547
LEDs (Different colors)
12volt Battery or 9volt
The switch S1 can be the existing changeover switch of the vehicle itself.
The circuit can be powered of the 12V available from the vehicle itself.
The color of the LED depends on your choice.
Assemble the circuit on a good quality PCB.
Be careful with the wiring of this circuit because any wrong connection may put the electricals of your vehicle in trouble.