Radiator Shutter Motor -V544-, Checking

General Description 

The Radiator Shutter Motor - V544- is used to control the mass air flow entering the lower air inlet. By closing the Radiator Shutter Motor - V544-, the head wind towards the radiator and into the engine compartment is reduced. This measure minimizes the warm-up cycle and, in addition, decreases the air resistance at the vehicle's radiator grille, thus reducing the drag coefficient (cd). At the beginning of the warm-up cycle, the Radiator Shutter Motor - V544- is closed and remains closed until the engine coolant temperature has reached a defined threshold value (80 °C). As soon as this temperature threshold has been exceeded, the Radiator Shutter Motor - V544- is opened to provide the required cooling. If the engine coolant temperature falls below the temperature threshold again during the driving cycle (e.g. due to engine stop phases during start/stop operation), the Radiator Shutter Motor - V544- is closed again. Outside of the warm-up cycle, the Engine Control Module -J623- determines the set point position of the Radiator Shutter Motor - V544- using the vehicle speed and the cooling requirement of single partial functions (e.g. engine, air conditioning, charge air).

Special Tools And Workshop Equipment Required 

• Multimeter.
• Wiring Diagram.
• Scan Tool.

Test Requirements 

• Fuses OK.
• Battery voltage OK.
• Switch OFF all electrical and electronic accessories.
• Vehicles with Auto. Transmission, ensure Selector Lever position is in "P".
• Vehicles with Man. Transmission, ensure Shifter Lever position is in "N" with Parking Brake applied.
• Observe all safety precautions: SAFETY PRECAUTIONS .
• View clean working conditions: CLEAN WORKING CONDITIONS .
• For Hybrid vehicles refer to: HIGH VOLTAGE SYSTEM GENERAL WARNINGS .