Your 2003 Honda CR-V uses Honda All Season Type 2 coolant in the radiator. This coolant is a pre-mixed blend of Honda antifreeze and water. Checking the coolant level, which helps protect the engine from overheating, should at least be done at every oil change. If necessary, top the coolant level off between oil changes to help keep your engine running at its optimal temperature.
Raise the bonnet of your CR-V. Lift the support rod and prop the bonnet out of the way.
Check the coolant level in the coolant reserve tank. The reserve tank, located beside the radiator, should read at the "MAX" level. If the fluid is below the "MAX" level, add coolant to the reserve tank to reach the "MAX" line.
Make sure the engine is cool. If the coolant is below the MIN line, slowly remove the radiator cap and check the coolant level in the radiator. Add coolant directly into the radiator if necessary to bring the coolant level back to the top.
Always use a 50-50 blend of antifreeze and water to help maintain the proper temperature.