2003 Subaru Impreza Owner's Manual - Page 345

Maintenance and service D Do not splash the engine coolant over painted parts. The alcohol contained in the engine coolant may damage the paint surface. J Engine coolant B Checking the coolant level J Cooling fan, hose and connections Your vehicle employs an electric cooling fan which is thermostatically controlled to operate when the engine coolant reaches a specific temperature. If the radiator cooling fan does not operate even when the engine coolant temperature gauge exceeds the normal operating range, the cooling fan circuit may be defective. Check the fuse and replace it if necessary. If the fuse is not blown, have the cooling system checked by your SUBARU dealer. If frequent addition of coolant is necessary, there may be a leak in the engine cooling system. It is recommended that the cooling system and connections be checked for leaks, damage, or looseness. 1) "FULL" level mark 2) "LOW" level mark Check the coolant level at each fuel stop. 1. Check the coolant level on the outside of the reservoir while the engine is cool. 2. If the level is close to or lower than the "LOW" level mark, add coolant up to the "FULL" level mark. If the reserve tank is empty, remove the radiator cap and refill as required. 11-16