Abstract: A timepiece device includes a control unit for time keeping, which is synchronizable by a clock generator. The timepiece device has at least two crystal oscillators built respectively by at least one crystal unit, whereby a first crystal oscillator with a first crystal unit and with a predetermined nominal oscillation frequency is suitable for use as the clock generator of the control unit during a vehicle standby mode, and whereby the oscillation frequency of the first crystal oscillator is at least temporarily measured and adjustable by a second crystal oscillator with a second crystal unit whose nominal oscillation frequency is higher than that of the first crystal oscillator. In a method of operation of the timepiece device, the oscillation frequency of the second crystal oscillator is compensated against the temperature by the software inside the control unit.