If the voltage of the MobilHybrid drops below the charging limit, the MobilHybrid must be charged again. If this occurs, the red LED lamp "Charging" lights up in the hinge window next to the PV fuses. At the same time, the contact in the AUX1 connector between pin 1 and pin 2 is closed. This is the signal to start the generator and supply the MobilHybrid with power at the input. The MobilHybrid switches off before the battery voltage drops too far to protect the battery from deep discharge.