Blower Motor Control
The climate control system has a variable blower speed control provided by a Variable Blower Control (VBC) module with an integral high blower relay. The customer has the option of manually selecting one of seven preset blower speeds from the control panel or selecting to operate the DATC in automatic mode.
In automatic mode, the blower speed is determined as a function of many input variables. Based on the desired in-vehicle temperature, the system constantly monitors the ambient temperature, discharge air temperatures, in-vehicle temperature and sun load levels then calculates the desired blower setting.
There are special conditions that affect the blower speed while in the automatic mode of operation.
In a cold ambient temperature condition, the DATC system implements a Cold EngineLockout (CELO) feature with the blower motor. For a cold vehicle interior, the DATC system will operate in low blower/defrost mode until the engine coolant temperature reaches a required value. Once the engine coolant has warmed up the blower motor will continue in the automatic mode.
At very high vehicle speeds (monitored via the SCP Vehicle speed status message), the DATC system may adjust the blower motor speed to maintain constant air flow. This may be necessary in situations where the ram air effects at high speed changes the air flow into the vehicle interior.
For vehicles fitted with a cellular phone, the DATC module may lower the blower motor speed to reduce the level of ambient noise in the vehicle interior when the phone is in use. The status of the cellular phone is monitored via the SCP cellular phone ON or off message.
Air Distribution Control
The climate control system has variable position control provided by the electrical motor actuators. The system gives the option of manually selecting one of five preset air distribution modes or operating the DATC system in automatic mode.
Climate Control - Battery Disconnection
The DATC will store the panel settings in volatile memory. Therefore, in the event of battery disconnection, or interruption of the supply, the information is lost. After reconnection, historical fault codes are available, and the panel will be set to off. An average automatic setting will be recovered when the DATC is next switched ON.
If the battery is disconnected, the panel settings will be lost. The customers non standards settings should be recorded and re-inputed before the vehicle is returned to the customer.