Radiator Shutter: Description and Operation

Active Grille Shutter System

The active grille shutter system (when equipped) is comprised of the grille shutter assembly and the grille shutter actuator. The active grille shutter system is primarily used to maximize fuel economy by reducing aerodynamic drag on the vehicle. In addition, the system is used to control coolant temperature, HVAC system performance and exhaust emissions depending on the vehicle speed. The system is also used to shorten engine warm-up time, increasing engine efficiency and providing heat to the vehicle occupants in a timely manner.

PCM inputs/outputs used for controlling the active grille shutter system are the:

- Engine Coolant Temperature (ECT) sensor

- Intake Air Temperature (IAT) sensor

- A/C pressure transducer

- Accelerator Pedal Position (APP) sensor

- ABS module, messages sent over the High Speed Controller Area Network (HS-CAN)

- Engine cooling fan motor

- Engine oil temperature

Grille Shutters

The grille shutters are several "slats" or "blinds" connected to one another by a linkage system. One of the individual grille shutters is fixed to the grille shutter actuator. When the grille shutter actuator moves, it moves the attached shutter which causes the other linked shutters to move. The individual grille shutters are not available for service separately, they are serviced with the grille shutter assembly.

Grille Shutter Actuator

The grille shutter actuator is a smart motor which receives position requests from the PCM via a Local Interconnect Network (LIN). One of the grille shutter blinds connects to the grille shutter actuator using a retainer. The grille shutter actuator can be serviced individually or as an entire assembly, which includes the grille shutters, grille shutter actuator, retainer and grille shutter housing. The grille shutter actuator positions the grille shutters based on commands received from the PCM. The full range of movement of the grille shutter actuator is a total of 90 degrees from fully closed to fully open. The actuator moves the grille shutters to 1 of 16 positions (approximately 6 degrees between positions) when requested by the PCM.