ATG EPS Mode D'emploi Et Entretien page 19

Power steering parts
The testing bench verify if the DC voltage is inside the range from 12Volt to 15 Volt, if it is out of range the following two message will
appear (Low voltage or Over voltage):
The actual DC voltage is showed in the 'Power Supply' box.
The DC voltage is set by means of DC power supply unit and a 100Ah Battery. You can adjust the voltage acting on the potentiometer
located in the power supply unit. We suggest to set it between 13Volt and 13.5 Volt.
ATG - Eps Testing system