Four Seasons 20049 A/C Trinary Switch

Four Seasons 20049 Trinary Pressure Switch

The Four Seasons Pressure Switch 20049 is a system-mounted A/C trinary switch built for 12-volt HVAC systems. It uses a 4-terminal, pin-style, male connector with a gray Weather Pack design and steel construction for dependable electrical and pressure control in the air conditioning circuit.

Key Features

• System-mounted trinary pressure switch for A/C clutch and compressor control
• 12-volt, 4-terminal, pin-type design with male connector
• Gray Weather Pack connection for secure electrical interface
• Male fitting with 3/8" x 24 thread size
• Steel construction with open/open pressure logic
• Meets or exceeds OEM requirements
• Cross-reference: Global Parts Distributors LLC 1711694

Product Details

This Four Seasons 20049 pressure switch monitors refrigerant pressure and helps manage compressor and condenser fan operation through trinary switching logic. It is designed for vehicles that use a system-mounted pressure switch with low, medium, and high pressure thresholds, including applications such as the Honda Passport, Isuzu Rodeo, Isuzu Axiom, Isuzu Trooper, Isuzu VehiCROSS, and Isuzu Amigo. The Four Seasons Pressure Switch line focuses on direct-fit HVAC service parts for restoring factory-style A/C control, and this part number 20049 follows that approach with OE-style electrical and thread specifications.

Common Repair Symptoms

• A/C compressor cycling incorrectly due to pressure switch failure
• Condenser fan not responding at the proper pressure range
• Intermittent A/C operation on Honda Passport or Isuzu Rodeo applications
• System pressure control faults in Isuzu Axiom, Trooper, VehiCROSS, or Amigo HVAC systems
• Loss of compressor cutout protection from an inaccurate trinary switch

Installation Notes

Verify connector style, thread size, and system-mounted location before installation. Confirm the vehicle uses a trinary pressure switch with the listed pressure thresholds: low on at 35 psi and low off at 28 psi, medium on at 225 psi and medium off at 180 psi, and high on at 280 psi with high off at 380 psi. Use proper refrigerant service procedures and inspect the A/C circuit for wiring, connector, and pressure-related faults during replacement.

Quality Assurance

Four Seasons 20049 is built to meet or exceed OEM specifications for fit and function in supported HVAC applications. It is engineered as a direct replacement pressure switch for system-mounted trinary control in compatible Honda and Isuzu vehicles.