Volvo XC90 TWIN ENGINE Owner's Manual page 254

KEY, LOCKS AND ALARM
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Turn the key over, move the button to
the side and slide the rear cover slightly
upward.
The cover will loosen and can be
removed from the key.
7 Included in vehicles equipped with keyless locking/unlocking*.
252
Use a screwdriver or similar object to turn
the battery cover counterclockwise so the
markers point to OPEN.
Remove the cover carefully by pressing
e.g. a fingernail into the indentation.
Pry the cover up.
The battery's positive side (+) faces
upward. Carefully pry out the battery as
shown in the illustration.
CAUTION
Avoid touching new batteries and their
contact surfaces with your fingers as this
will impair their function.