Four Seasons 35931 Engine Cooling Fan Switch

Engine Cooling Fan Switch for Ford and Mercury

Four Seasons 35931 is an engine-mounted temperature switch for cooling fan control. It uses a male connector with an open connector shape and a 3/8" pipe thread, making it a direct-fit style replacement for select Ford and Mercury applications.

Built to meet or exceed OEM requirements, this Four Seasons Temperature Switch is specified for cooling fan operation at 220°F off and 228°F on. It is a practical replacement for vehicles such as the Ford Mustang, Ford LTD, and Mercury Capri where accurate fan cycling is critical to engine temperature management.

Key Features

• Four Seasons Temperature Switch, part number 35931
• Engine-mounted cooling fan switch for temperature-based fan control
• Male connector with open connector shape
• 3/8" pipe thread fitting, 43/64" x 18
• Temperature off at 220°F and on at 228°F
• Meets or exceeds OEM specifications
• Compatible with select Ford Mustang, Ford LTD, Mercury Capri, and related applications

Product Details

Four Seasons 35931 is a temperature switch used in engine cooling fan circuits to trigger fan operation at the specified coolant temperature range. The switch mounts on the engine and is listed with a single terminal, male fitting gender, and open fan state. For buyers searching for a Ford Mustang cooling fan temperature switch, Ford LTD engine mounted coolant fan switch, or Mercury Capri temperature switch, this part number provides a focused OE-style replacement option.

This part cross-references DENSO Auto Parts 5031 and Gates 22733 for the same application.

What It Helps Address

• Cooling fan not switching on at the correct temperature
• Fan cycling too early or too late
• Overheating caused by inaccurate temperature signaling
• Faulty engine-mounted coolant fan switch operation
• Replacement needs for aging Ford and Mercury temperature switch systems

Installation Notes and Tips

• Verify the 3/8" pipe thread and single-terminal connector before installation.
• Confirm the vehicle uses an engine-mounted temperature switch location.
• Match the temperature range to the original fan control specification.
• Inspect the connector and wiring for corrosion or looseness before installing the new switch.

Quality Assurance

Four Seasons 35931 is manufactured to meet or exceed OEM requirements for the listed cooling fan switch applications. It is a temperature-based replacement part for select 1980-1986 Ford and Mercury vehicles, including Ford Mustang, Ford LTD, Mercury Capri, and related models.