Air Conditioning: Notes

WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

The A/C refrigerant system is a clutch cycling Thermostatic Expansion Valve (TXV) type. The system components are the following:

A/C compressor
A/C compressor clutch assembly
A/C condenser core with integrated receiver/drier
Receiver/drier desiccant cartridge
TXV
A/C evaporator core
Connecting refrigerant lines

The refrigeration system operation is controlled by the following:

Evaporator temperature sensor
A/C pressure transducer
TXV

The refrigerant system incorporates an A/C compressor controlled by the PCM through an A/C clutch relay. The HVAC module sends an A/C request signal over the Medium Speed Controller Area Network (MS-CAN) to the Smart Junction Box (SJB) which relays the request to the PCM over the High Speed Controller Area Network (HS-CAN). An evaporator temperature sensor is used to disengage the A/C compressor clutch when the evaporator core temperature falls to a temperature near freezing.

An A/C compressor pressure relief valve is installed in the A/C compressor to protect the system against excessively high refrigerant pressures as a redundant backup to the A/C pressure transducer. A TXV is used to meter the liquid refrigerant into the A/C evaporator core.