Four Seasons
Temperature Switch

Four Seasons 37378 Engine Cooling Fan Temperature Switch

Brand Four Seasons 37378
Connector Gender Male
Connector Shape Round
Description Switch-Temp /Radiator Mount
Function temperature switch
Meets / Exceeds OEM? YES
Mnt Sys Loc System Mount
Style Temperature
Terminal Quantity 1
Type Temperature
Product line Temperature Switch
Fits Toyota and Plymouth · 5 vehicles

OE direct replacement. Meets or exceeds OEM requirements for dependable cooling control.

Temperature switch. Monitors heat and helps trigger cooling system operation.

Round connector. Single-terminal, male connection for straightforward installation.

Cross-references Four Seasons 37378, A03778 and SW543 for the same application. See all 3.

$76.80Free shipping
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Four Seasons 37378 Temperature Switch

Four Seasons 37378 is an engine cooling fan temperature switch for radiator-mounted applications. It uses a round, male connector with a single terminal and is built to meet or exceed OEM requirements for direct replacement service.

Key Features

  • Engine cooling fan temperature switch for radiator mount use
  • Round connector shape with male terminal design
  • Single-terminal electrical connection
  • System mount style with temperature-based operation
  • Meets or exceeds OEM specifications
  • Four Seasons 37378 temperature switch for service replacement

Product Details

This Four Seasons Temperature Switch line focuses on temperature-controlled cooling system operation, helping the fan circuit respond to radiator temperature changes. Part number 37378 is a direct-fit style replacement for vehicles that use a radiator-mounted temperature switch, including Fits 1981-1984 Toyota Starlet, N/A and Fits 1983 Toyota Corolla, N/A. This part cross-references A03778 and SW543 for the same application. For Toyota Starlet and Toyota Corolla cooling system service, Four Seasons 37378 provides the correct connector style, terminal count, and mounting format for the specified application.

Common Issues This Part May Address

  • Cooling fan not switching on at the proper temperature
  • Intermittent fan operation caused by a failing temperature switch
  • Radiator fan control problems in temperature-based systems
  • Electrical connection issues from a worn or incorrect connector style
  • Replacement needs during Toyota Starlet or Toyota Corolla cooling system repair

Installation Notes and Tips

Verify the connector shape, terminal quantity, and mounting location before installation. This switch is specified as a radiator-mount, system-mount temperature switch, so match the original sensor location and electrical connection on the vehicle. Confirm fitment for the exact year and model listed before ordering, including Fits 1981-1984 Toyota Starlet, N/A and Fits 1983 Toyota Corolla, N/A.

Quality Assurance

Four Seasons 37378 meets or exceeds OEM specifications for the listed application, supporting accurate replacement selection for cooling fan temperature switch service.

This part fits 5 vehicles
Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.
YearMakeModelTransmissionPositionNotes
1984ToyotaStarlet—N/ATemperature Switch
1983ToyotaCorollaManualN/ATemperature Switch
1983ToyotaStarlet—N/ATemperature Switch
1982ToyotaStarlet—N/ATemperature Switch
1981ToyotaStarlet—N/ATemperature Switch
Directly replaces or cross-references 3 part numbers
Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.
Four Seasons — 37378A03778SW543