Ford Mustang (1999-2004) Service Manual: Dual-Function Pressure Switch (4.6L)

The dual-function pressure switch is used to interrupt A/C compressor operation in the event of high system discharge pressures.
- The dual-function pressure switch is mounted on a Schrader valve-type fitting on the high pressure side of the A/C manifold and tube.
- It is not necessary to discharge the refrigerant system to remove the dual-function pressure switch.
- A valve depressor, located inside the threaded end of the dual-function pressure switch, presses on the Schrader valve stem.
- This allows the dual-function pressure switch to monitor the compressor discharge pressure.
- When the compressor discharge pressure rises, the switch contacts open, disengaging the A/C compressor. When the pressure drops, the contacts close to allow operation of the A/C compressor. For specifications regarding operating pressure(s), refer to Section.
The dual-function pressure switch has a second set of electrical contacts used for high-speed cooling fan control.
When the compressor discharge pressure rises, the contacts close and engage the high speed fan control. When the pressure drops, the contacts open and the high speed fan control is disengaged.
Refrigerant Containment Switch (3.8L)
The refrigerant containment switch is used to interrupt A/C compressor operation in the event of high system discharge pressures.
- The refrigerant containment switch is mounted on a Schrader-type valve fitting on the high pressure side of the compressor manifold and tube assembly.
- A valve depressor, located inside the threaded end of the refrigerant containment switch, presses on the Schrader valve stem.
- This allows the refrigerant containment switch to monitor the A/C compressor discharge pressure.
- When the A/C compressor discharge pressure rises, the switch contacts open, disengaging the A/C compressor. When the pressure drops, the contacts close to allow operation of the A/C compressor. For additional information regarding operating pressure(s), refer to Section.
- It is not necessary to discharge the refrigerant system to remove the refrigerant containment switch.
Suction Accumulator
NOTE: Installation of a new suction accumulator is not required when
repairing the air conditioning
system except when there is physical evidence of contamination from a failed A/C
compres ...
Spring Lock Coupling
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
f ...
Other materials:
Oil Level Indicator and Tube
Removal and Installation
1. Remove the oil level indicator.
2. Remove the LH exhaust manifold. For additional information, refer to Exhaust
Manifold LH in
this section.
3. Remove the bolt.
4. Remove the oil level indicator tube.
5. To install, reverse t ...
Removal
1. Disconnect the battery ground cable.
2. Remove the air cleaner outlet tube. For additional information, refer to
Section.
3. Remove the radiator sight shield.
4. Install the special tool.
5. Using the special tools, support the engine.
6. Raise and sup ...
Engine and Radiator Flushing
Special Tool(s)
Coolant System
Drain/Flush/Fill
164-R3673 or equivalent
Flush Kit
164-R3658 or equivalent
Drain Kit
164-R3662 or equivalent
Material
Item
Specification
Motorcraft Premium Cooling
...
