Defrost Mode Buick Century VI

Defrost Mode

When the operator selects Defrost, the following occurs

1. The mode actuator has vacuum applied to it through the Brown vacuum line, pushing the vent door closed.
2. The defrost actuator has vacuum applied to it through the Yellow vacuum line, pushing the defrost door open and closing the heater door through mechanical linkage.
3. A/C is forced ON.
4. Recirculation is not available.