Displaying Faults And Reading Faults - ATC System
WARNING: This page is about a different car, the 2005 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.
Use a scan tool to display DTCs stored in the A/C-heater control of the ATC system. (Refer to ELECTRONIC CONTROL MODULES - ELECTRICAL DIAGNOSTICS for more information)