tomtom wont start

[kcd]

when turned on set a destination, just says waiting for valid gps signal and does nothing else.tomtom go live 825

 

[dhn]

Is the battery fully charged?

Try a drum reset on the unit by holding the power button about 20 seconds till you hear the drum sounds.

Also, put the device in a stationary position OUTSIDE in a clear area and see if the signal gets picked up in a few minutes.

 

[canderson]

Since the 825 is a "Nav3" generation device, it still has a rudimentary satellite survey available.
While in a clear sky (outdoors), under "Settings", go to "Connections" and then "GPS status". As dhn recommends, wait a few minutes out there (as many as 12 minutes), and see whether the device shows anything more than the single little yellow circle at the north end of the compass, or whether other satellites appear.