Cold Start is performed every time when the GPS module is turned off without backup power supply connected. It is the longest starting time out of the three and usually takes 35 seconds in average under open sky environment. During Cold Start, almanac and ephemeris data has to be downloaded first from the GPS satellites to GPS module before a position fix can be acquired.

Assuming that a proper backup power source is provided, GPS module will perform Hot Start if the GPS module is powered on any time within the 2-hour time frame after GPS was previously turned off, as the ephemeris and almanac data is still stored inside the its flash memory.

Warm Start is performed if the above module is started after the 2-hour time frame, as part of its satellite data has to be refreshed.