Cadillac 2006 STS - Manual (Page 127)

This feature allows you to change the language that
the vehicle (instrument panel cluster, HUD, Navigation
system, DIC, etc.) is in. The languages available are
US English (male speaking voice) US English (female
speaking voice), UK English, German, French, Italian,
and Spanish.
To change the language, do the following:
1. Select the CONFIG hard key.
2. Touch the Vehicle screen button.
3. Select the globe screen button or choose the
desired language.
4. Your choice will be stored automatically.
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