Theory Of Operation
WARNING: This page is about a different car, the 2013 Dodge Avenger and 2013 Chrysler 200. However, it is still accessible from the selected car via links, so may be relevant.
When the ignition switch is on, the Totally Integrated Power Module (TIPM) sends a 12 Volt signal to the Powertrain Control Module (PCM) on the A/C Clutch Relay Control circuit. The PCM grounds this signal to indicate a request for A/C Compressor Clutch operation.