If you reset the GPS system, you should keep the car still for up to half an hour with the navigation system turned on, until you get at least three satelites. Only then you should drive the car for a while, then to calibrate the MK system.

When a GPS system (any GPS) is reset, it might take a while to download the "catalog". The same happens if you turn the GPS off in a location and turn it back on is a remote location (like when flying somewhere). The "catalog" is like a star map of the GPS satelittes that the GPS needs to know to discover the next frequency to listen to. In simple words, of course.

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