My garmin c510 cannot find any sats?

Question

brand new have downloaded softare update and pio

Answer 1

If it's brand new it may take up to 15 minutes to acquire the ephemeris data (the position of all available satellites in the sky). During this phase it needs a clear view of the open sky. Once it has initialised it will only need to re-acquire this data if it is moved more than about 600 miles from home. If it is genuinely broken, however, take it back under warranty