Automatic Temperature Control (ATC)
Each of the A/C heater controls in the Integrated Center Stack (ICS) are resistor type controls. When a button is pushed, or a knob is turned, the ICS sends a resistive signal over hard wired circuits to the Uconnect® touchscreen in the Radio Receiver Module (RRM). The controls in the Uconnect® touchscreen in the RRM mimic the action selected on the ICS. The RRM communicates the heater and A/C control request signals to the Heating, Ventilation and Air Conditioning (HVAC) module.
The HVAC module is a dedicated microcontroller that automatically drives the electrically operated air-door actuators for the Dual Zone Automatic Temperature Control (ATC) heating and A/C systems. The ATC HVAC module obtains sun load, in-car temperature and evaporator temperature information through hard wired circuits, and occupant heating and A/C settings and other required vehicle information over the Controller Area Network (CAN) data bus. Refer to MODULE, HVAC, OPERATION .
The Dual Zone ATC heating and A/C system is diagnosed using a scan tool. Refer to DIAGNOSTIC CODE INDEX .
Prior to replacing an A/C heater control or HVAC module, check for any Diagnostic Trouble Codes (DTCs) related to the heating and A/C system, and run the calibration procedure to verify that the concern is not an air-door calibration issue. Refer to STANDARD PROCEDURE .
The individual A/C heater controls located in the ICS cannot be adjusted or repaired. If an A/C heater control or control indicator lamp is inoperative or damaged, the entire ICS must be replaced. Refer to MODULE, INTEGRATED CENTER STACK (ICSM), REMOVAL .
The individual A/C heater controls located in the RRM touchscreen cannot be adjusted or repaired. If an A/C heater control or control indicator lamp is inoperative or damaged, the entire RRM must be replaced. Refer to MODULE, RADIO RECEIVER, REMOVAL .