Car Battery Failure Detector

Tools Required

Solder iron, Soldering wire, Soldering Paste, Wire Cutter, Desoldring Pump

COMPONENTS REQUIRED

Capacitor  10 micro farad 35Volts(1)

1 Kilo Ohm resistor (1)

1o Kilo Ohm resistor (2)

5.6 Kilo Ohm resistor(1)

1.5 Kilo Ohm resistor(2)

4.7Mega Ohm resistor(1)

 2.2 Kilo Ohm resistor(1)

10 Kilo Ohm variable resistor(1), LED 12Volt Flashing (1)

LED Green/Red or Green/Yellow(1), LM336Z-2.5(1), IC2:LM358(1), C106D(1), Push switch(1), Prototype wire, 5mm Red and Black wire, 12Volts DC source

Description

         A car battery deteriorates in use and its life seldom exceeds four years. When new, its voltage may drop to only 2V while cranking the engine. As the battery ages, its internal impedance increases and so the voltage drop while cranking also increases, until ultimately the drop is high enough to prevent the engine from starting. This gradual increase in voltage drop while cranking can be used as an early warning of looming battery failure and so this circuit indicate red/yellow light when the battery voltage drops to 8V.