0 Fuse Status Indicator Circuit

What this circuit do is provide status on the fuse installed thus it can help you in saving your time in troubleshooting especially when the problem is only the fuse (common problem). You can use this in your automobile or any DC devices powered by 12V battery. The circuit operation is summarized below.
1. Steady LED light - fuse is okay
2. Blinking LED (around 3 flashes per second) - fuse is broken
3. Off LED - no DC supply or the circuit is defective

schematic diagram
2N2222 pin
Part List:
Q1, Q2, Q3 - 2N2222 or similar NPN transistor
R1, R4 - 2.7 kilo ohms 1/4W
R2, R3 - 56 kilo ohms 1/4W
R5 - 1.2 kilo ohms 1/4W
R6 - 470 ohms 1/4W
C1, C2 - 4.7uF electrolytic capacitor rated 16V
D1, D2 - 1N4001 or any diode
LED - red or any low LED (see LED pinout in case you forget)

Other similar circuits:
Simple blown fuse indicator - Used in 220V AC circuits
Broken fuse indicator - DC fuse indicator circuit


Post a Comment