The invention relates to a method for initializing a control of a supply voltage of a light source, such as a laser diode, the light source being arranged in a first circuit configuration having an associated first reference voltage level or the light source being arranged in an alternative second circuit configuration having an associated alternative second reference voltage level, the method comprising the steps of gradually changing the supply voltage into the direction of the first reference voltage, measuring a light emission of the light source while gradually changing the supply voltage, if no light emission is measured: starting the control of the supply voltage of the light source after the first reference voltage has been reached and if a light emission is measured gradually changing the supply voltage into the direction of the second reference voltage and starting the control of the supply voltage of the light source after the second reference voltage has been reached.