The tolerance of RTC depends on the tolerance of RTC Input Clock basically. The Watch Crystal Oscillator (WCO), LPECO, or ILO can be used for RTC Input Clock.
If the external oscillator is used for the RTC Input Clock, the accuracy of external oscillator is RTC tolerance. If ILO is used for RTC Input Clock, the accuracy of ILO is the tolerance of RTC.
See the device datasheet for ILO AC Specifications.
RTC in Traveo II device supports 512 Hz, 1 Hz, and 2 Hz of calibration waveform output. The accuracy of the RTC is improved by calibrating the WCO or LPECO. The CLK_LF can also be calibrated. See Section 21.7 WCO/LPECO Calibration of the Traveo II Automotive Body Controller Entry Family Architecture Technical Reference Manual (002-19314 Rev. *F).
If the temperature calibration has to be considered, it is necessary to monitor Calibration waveform at RTC_CALL output pin for each experimental temperature (for example, -40℃, 25℃, 105℃) condition and compare it with an ideal reference waveform for each temperature condition.