The Dual Shield Low Voltage Disconnect (LVD) is designed to drastically reduce the parasitic drain on the vehicle’s batteries. Parasitic loads are caused by electrical devices such as interior lights, radios, child safety devices, etc. While these devices are critical to operation, there is a risk that the parasitic drain will be enough to discharge the battery and keep the vehicle from starting. The Dual Shield shuts off parasitic loads either by voltage or by time, depending on the model. While the ignition is on, the Dual Shield will not impact any of the electrical devices.Built-in LEDs indicate system status.