Four Seasons 20928 A/C Trinary Switch

Four Seasons 20928 Trinary Pressure Switch

The Four Seasons Pressure Switch 20928 is a system-mounted A/C trinary switch built for 12-volt HVAC systems. It monitors refrigerant pressure and helps control compressor and fan operation in Toyota, Lexus, Acura, and Chevrolet Prizm applications.

Key Features

• System-mounted trinary pressure switch for A/C clutch and compressor control
• 12-volt design with 4-pin terminal layout and male connector
• Female M11 x 1.00 threaded fitting for direct system installation
• Pressure operating points: low on 37 psi, low off 32 psi, medium on 225 psi, medium off 185 psi, high on 370 psi, high off 440 psi
• Steel construction with Weather Pack sealing
• Meets or exceeds OEM requirements
• Four Seasons 20928 cross-references UAC SW9726C for the same application

Product Details

This Four Seasons Pressure Switch line is built for HVAC pressure management in vehicles that use a trinary switch to protect the compressor and regulate condenser fan response. Part number 20928 is used in a wide range of import and domestic applications, including 1994-2001 Toyota Camry, 1996-2000 Toyota RAV4, 1995-2005 Lexus GS300, and 1996-2004 Acura RL. It also serves other Toyota and Lexus platforms such as the Corolla, Celica, Supra, ES300, LS400, SC400, and Sienna, along with the Chevrolet Prizm.

Compatible vehicle coverage includes long-tail searches such as Toyota Camry A/C trinary pressure switch replacement, Lexus GS300 HVAC pressure switch, and Acura RL compressor pressure switch. The Four Seasons 20928 is a direct-fit style pressure switch for systems that require the specified M11 x 1.00 threaded connection and 4-terminal electrical interface.

What It Helps Address

• A/C compressor cycling caused by incorrect refrigerant pressure readings
• Condenser fan control issues tied to pressure switch failure
• High-pressure cutoff faults in the HVAC system
• Low-pressure cutoff conditions that interrupt compressor operation
• Intermittent A/C performance on Toyota, Lexus, Acura, and Chevrolet Prizm vehicles

Installation Notes and Tips

Verify the connector style, terminal count, and M11 x 1.00 fitting before installation. This switch is system mounted and uses a female threaded fitting with a male electrical connector, so matching the original configuration is important for proper operation. Confirm vehicle-specific fitment for the exact year and model, including the 1998-2003 Toyota Sienna note that excludes Tow Package vehicles.

For best results, compare the original switch’s pressure thresholds and connector layout to the replacement part before service. Four Seasons 20928 is commonly searched as an A/C pressure switch for Toyota Camry, Lexus ES300, and Acura TL HVAC repair.

Quality Assurance

Four Seasons lists this pressure switch as meeting or exceeding OEM requirements. The steel housing, Weather Pack sealing, and OE-style electrical and pressure specifications support consistent HVAC system operation across the listed applications.