Volvo Repair: coolant, visible loss, turbo wagon

Question
My low coolant light came on though the reservoir is full BUT i'm smelling what i believe (strongly) to be a leaky heater core.  No visible loss of coolant nor smell in engine compartment. I put some radiator junk in last week.  COuld it have gummed something up or ? Shall I not drive until all issues resolved? 1999 V70 turbo wagon
Thanks!

Answer
Dann, I would pressure test the system to be sure.  While its under pressure, remove the drivers panel, then remove the black cover so you can access the core.  You would be able to see if its leaking.  You can drive it but you would have to deal with the smell.  Its not a badly priced repair.  Roger