Theory of Operation
WARNING: This page is about a different car, the 2011 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.
The Powertrain Control Module (PCM) receives various information from the operator controls and A/C system to determine when the A/C Compressor Clutch should be turned on. The Totally Integrated Power Module (TIPM) receives a signal from the PCM to turn on the A/C Compressor Clutch. The TIPM supplies 12 Volts to the A/C Compressor Clutch which has a dedicated ground circuit. You will not receive a MIL lamp for this fault, but the customer may complain of poor A/C performance.