ATC Automatic Temperature Control Systems Click Here to Download all of the files listed below as a compressed zip file! All Files require a PDF Viewer to View Theory of Operation ATC Component Troubleshooting Power Module Programming Schematic- ATC System 1999 Vacuum System Troubleshooting Vacuum Diagram and Logic Charts Air Conditioning Troubleshooting Heater Troubleshooting ATC Systems Diagnostics Initial Operation and Road Test Procedure Functional Testing and Diagnostics Return to HVAC System Trouble Shooting Guides Technical Support Home Page