Heater problem
1999 Mercury Sable 6 cyl Four Wheel Drive Automatic 153,00 miles

My heater in my Mercury Sable won't work after several attempts at a shop. So, I purchased a portable heater that plugs in to my cigarette lighter. The package says to read my owners manual, which I have never had, to make sure my car will be able to maintain the use of the heater.

It states that I need to make sure the fuse is no more than 15 amps and that my car can handle the heater. The heater is a 12 volt heater.

Because I don't have my manual, how can I be sure that the car will be able to handle the heater without causing a fire.

Very cold in Indiana,
Toni