A/C Cycling Switch

WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying A/C Cycling Switch

Courtesy of FORD MOTOR CO.

The A/C cycling switch is mounted on a Schrader valve-type fitting on the side of the suction accumulator.

A valve depressor, located inside the threaded end of the A/C cycling switch, presses in on the Schrader valve stem.
This allows the suction pressure inside the suction accumulator to control the operation of the A/C cycling switch.
The electrical switch contacts open when the suction pressure drops, the contacts close when the suction pressure rises. For specifications regarding operating pressure(s), refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION .
When the A/C cycling switch contacts close, the A/C request signal circuit is completed to the PCM.
When the A/C cycling switch contacts open, the A/C request signal circuit is interrupted and compressor operation stops.
The A/C cycling switch will control the A/C evaporator core pressure at a point where the plate/fin surface temperature will be maintained slightly above freezing.
This prevents icing of the A/C evaporator core and blockage of air flow.
It is not necessary to discharge the refrigerant system to remove the A/C cycling switch.
A/C Pressure Cutoff Switch

Fig 2: Identifying A/C Pressure Cutoff Switch
Courtesy of FORD MOTOR CO.

The A/C pressure cutoff switch is used to interrupt the A/C compressor operation in the event of high system discharge pressures.
The A/C pressure cutoff switch is mounted on a Schrader valve-type fitting on the high pressure side of the A/C manifold and tube.
A valve depressor, located inside the threaded end of the A/C pressure cutoff switch, presses on the Schrader valve stem.
This allows the A/C pressure cutoff switch to monitor the compressor discharge pressure.
When the compressor discharge pressure rises, the switch contacts open and the A/C request signal circuit to the PCM is interrupted. When the pressure drops, the contacts close to complete the A/C request signal circuit to the PCM. For specifications regarding operating pressure(s), refer to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION .
It is not necessary to discharge the refrigerant system to remove the A/C pressure cutoff switch.
Spring Lock Coupling

Fig 3: Identifying Spring Lock Coupling Components
Courtesy of FORD MOTOR CO.

The spring lock coupling is a refrigerant line coupling held together by a garter spring inside a circular cage.
When the coupling is connected together, the flared end of the female fitting slips behind the garter spring inside the cage of the male fitting.
The garter spring and cage then prevent the flared end of the female fitting from pulling out of the cage.
Three O-ring seals are used as a seal between the two halves of the A/C condenser core couplings, all other couplings have two O-ring seals.
Use only the O-ring seals listed in the Ford Master Parts Catalog for the spring lock coupling.
A plastic indicator ring is used on the spring lock couplings of the A/C evaporator core to indicate, during vehicle assembly, that the coupling is connected. Once the coupling is connected, the indicator ring is no longer necessary but will remain captive by the coupling near the cage opening.
The indicator ring may also be used during service operations to indicate connection of the coupling.
An A/C tube lock coupling clip may be used to secure the coupling but is not required.