where is my coolant going on 2003 Volvo S60

the low coolant message is coming up often. the coolant is container is empty when this message does come up

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2 answers
Keep the coolant reservoir filled up, and have the vehicle checked for a coolant leak. It's common for the radiator to leak on these, so check that, and the water pump and the heater core too.
buy a heater core off the web and check this out:

http://www.volvo-forums.com/t22870-1998-volvo-v70-heater-core-replacement-w-pics.htm