There should be a coolant reservoir bottle on your vehicle as well. Find the radiator cap and you should see a small rubber tube that leads to this reservoir.
On this bottle you will see two lines. One says full hot and the other full cold. If you can't see through the bottle then open the top and look in. Make sure that you fill this with a 50/50 mix of coolant and water. Never put in straight coolant.
If you have an owner's manual for this vehicle it's best to check what type of coolant to use. Many manufacturers require their own coolant.
Also it's best to change the coolant every 30,000 miles or 2 years. If you haven't done this, have it done and they can point out the reservoir to you for the future.
Hope this helps.
〉 Answered on Jun 26th, 2008 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines