VIETA CDV7500GP Owner's Manual page 67

Navigation Operation
If you enter or exit a multi-
storey car park or similar
using a spiral ramp.
If your vehicle's wheels
spin, such as on a rough
track or in snow.
If trees or other obstacles
block the GPS sig-nals
for a considerable period.
If your vehicle is turned on
a turntable or simi-lar
structure.
If you put on chains or
change your tyres for
ones with a different size.
If you drive very slowly, or
in a start-and-stop manner,
as in a traffic jam.
BR - 67