However, the function can be more sophisticated depending on the system:
* In some vehicles, the fuel pump is controlled by the engine control unit (ECU) and there is no separate fuel pump switch. The ECU activates the pump only when needed (e.g., when the ignition is on or the engine is cranking).
* In older vehicles or some specialized applications, a manual fuel pump switch might be used for safety or troubleshooting. This allows the mechanic or owner to isolate the fuel pump for testing or to prevent fuel flow during maintenance.
* Some vehicles have an inertia switch: This is a safety device that shuts off the fuel pump in the event of a collision to help prevent a fire. It's a type of fuel pump switch that's automatically activated.
In short, while not universally present in modern cars, a fuel pump switch's primary purpose is to control the power supplied to the fuel pump, thus controlling the flow of fuel to the engine.
