Air Conditioning Cycling Switch (ACCS) Circuit
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The ACCS circuit to the powertrain control module (PCM) provides a voltage signal which indicates when A/C is requested. When the A/C function selector switch is turned on, voltage is supplied to the ACCS circuit at the PCM. Refer to SYSTEM WIRING DIAGRAM for vehicle wiring.
If the ACCS signal is not received by the PCM, the PCM does not allow the A/C to operate.