A/C Request
WARNING: This page is about a different car, the 2013 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
When the A/C is requested, the HVAC module sends the message over the MS-CAN to the BCM. The BCM sends the A/C request through the HS-CAN to the PCM.
When an A/C request is received by the PCM, the PCM engages the A/C clutch relay when:
- the refrigerant pressure isn't excessively high or low.
- the engine coolant temperature isn't excessively high.
- the ambient air temperature is above 6 C (43 F).
- a WOT condition is not present.
- the evaporator discharge air temperature is above 7 C (45 F).