Abstract: A method for determining the actual frequency of an inaccurate clock signal then using the actual frequency to generate a compensation factor to correct calculations using the clock signal. The method includes counting the number of clock pulses in the clock signal over a predetermined and programmable period of time, and based on the clock pulse count, determining the actual frequency of the clock signal. Once the actual frequency of the clock signal is determined, this value is used to generate the compensation factor based on the expected or rated frequency of the clock signal to compensate for the calculations using the clock signal. The method has a particular application for use in a powertrain control module incorporating a low frequency resonator and a high frequency system clock, where the resonator generates an inaccurate clock signal which is highly stable for short periods of time and the system clock is relatively stable over long term but suffers from short term jitter.