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How Hybrid System Indicators Work

Hybrid Fuel and Energy Displays
Hybrid system indicators are a big leap from old fuel gauges in terms of how much data they display.
Hybrid system indicators are a big leap from old fuel gauges in terms of how much data they display.
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The fuel gauge within the instrument cluster from an older gas-powered car is clearly one of the most important pieces of information a driver needs to monitor. This rather simple device works with the help of a sending unit inside the car's fuel tank. This consists of a small foam float connected to a thin metal rod, which wipes against an electrical device called a resistor as the gas level decreases. The resistor sends an electric current to the fuel gauge, and the results are displayed via the small needle every driver uses to tell whether the gas tank is full or empty. As the fuel level decreases and the float moves downward with it, the metal rod, or wiper, moves across the resistor -- the farther along it moves, the stronger the electric current is. And the stronger the electric current is, the closer to empty your tank is, too.

Newer cars use microprocessors to read the resistor and communicate this information -- hybrid cars aren't any different. Computers are behind much of how hybrid system indicators collect, calculate and display information, especially since most hybrid drivers want to know things like battery life and fuel economy in addition to how much gas is left in the tank. The main draw to hybrid system indicators is that they're multi-informational -- they present the driver with not just one or even a few pieces of information but many, many bits of valuable data. These features are typically customizable and can reflect a wide range of statistics.

Because hybrids use a combination of an electric motor and gasoline engine, the main focus of a hybrid system indicator is usually the battery level, the gas level and the dynamic between the two. Hybrids measure battery life using volt meters or computers to send the flow of amps to the display unit. The traditional fuel sender unit, along with fuel temperature sensors and more sophisticated vehicle inclination sensors, determines gas levels and sends the information to a microprocessor. This information is sent directly to the fuel display for the driver to see. The computer also continuously takes the car's average miles per gallon reading to determine how efficiently the engine is operating.

So how can all of this make you a better driver? Keep reading to find out.