Info please
 

My daughter has a 2006 Volvo XC90 and as of this morning her battery is dead. She said the fan keeps blowing even after vehicle was shut off and she could not lower the heat temperature of the blower. Any suggestions would truly be appreciated

she can pull the 30A fuse to the blower (check owners manual for location) to at least keep the battery alive until she can have the car looked at. Most likely cause is a stuck relay but could be a switch or a shorted blower resistor.

Volvo's are known to be haunted with electrical issues, and I would check for water in foot wells first, and if you find moisture, then that is shorting out blower resistor, or worse, the CEM is wet which can cause all sorts of wacky issues. Sun roof drains being clogged is common problem, or your windshield wiper cowl drains are plugged, so check for moisture first.