A1: Lubrication and Cooling Systems Diagnosis and Repair Active Grill Shutters Change Engine Oil Check Cooling System Voltage Coolant Flow-World Engine Both Thermostats Open Coolant Refractometer Coolant Replacement Coolant Test Coolant Test Test Strips Coolant Test, Simple Hydrometer Cooling Fan Tests Engine Oil Circulation Engine Oil Level Quality Sensor Engine Oil Selection External Gear Oil Pump Fan Clutch Checks Fan Motor Checks Gerotor Pump Internal-External Gear Pump with Crescent Measure Gerotor-Type Pump Oil Filter Oil Flow-World Engine Oil Pressure Test Overheating Causes Pressure Cap Operation Pressure Test Cooling System Radiator Remove and Replace Replace Thermostat Rotor Oil Pump Rust & Corrosion Rust & Corrosion Protection Conventional Test Radiator Cap Thermostat Electric Assist Thermostat Operation Thermostat Remove and Replace Water Pump Operation