Four Seasons 20929 HVAC Binary Switch

Four Seasons 20929 Pressure Switch

The Four Seasons Pressure Switch 20929 is a system-mounted HVAC binary switch built for precise refrigerant pressure monitoring. It uses a rectangular male connector, a 2-terminal Weather Pack design, and an M11 x 1.00 fitting thread size for a direct service replacement on supported Toyota, Lexus, and Mitsubishi applications.

Four Seasons Pressure Switch line components are built for HVAC service work where accurate pressure control matters. This Four Seasons 20929 switch meets or exceeds OEM requirements and is designed for vehicles that use an open, binary pressure switch configuration.

Key Features

• Binary HVAC pressure switch for system-mounted applications
• Rectangular male connector with 2 terminals
• Weather Pack sealed connection for improved environmental protection
• Steel construction with gray finish
• M11 x 1.00 fitting thread size
• Operate pressure range: 28 psi off, 29 psi on
• Meets or exceeds OEM specifications

Detailed Description

This pressure switch is used in HVAC systems that rely on a binary pressure signal to help manage compressor operation based on refrigerant pressure. The open-contact design, system-mounted layout, and sealed connector make it a practical replacement for service on Toyota 4Runner, Tacoma, Tundra, Land Cruiser, Supra, T100, and Lexus GX460 applications, along with select Mitsubishi models. The Four Seasons 20929 is also cross-referenced to UAC SW4003C for the same application.

Fits 2010-2021 Toyota 4Runner, Pressure Switch. Fits 1995-2016 Toyota Tacoma, Pressure Switch. Fits 2000-2016 Toyota Tundra, Pressure Switch. Fits 1998-2004 Toyota Land Cruiser, Pressure Switch. Fits 1993-1998 Toyota Supra, Pressure Switch. Fits 1993-1998 Toyota T100, Pressure Switch. Fits 1994-2006 Mitsubishi Montero, Pressure Switch. Fits 2001-2006 Mitsubishi Montero Sport, Pressure Switch. Fits 2001-2005 Mitsubishi Eclipse, Pressure Switch. Fits 2000-2003 Mitsubishi Diamante, Pressure Switch. Fits 1995-2000 Lexus SC300, Pressure Switch. Fits 1994-1996 Toyota Previa, Pressure Switch. Fits 1994 Lexus SC300, Pressure Switch. Fits 2010-2013 Lexus GX460, Vehicle w/o Rear AC; Pressure Switch. Fits 2014-2017 Lexus GX460, Not compatible with dual-zone climate control.; Pressure Switch. Fits 2018-2021 Lexus GX460, Vehicle w/o Rear AC; Pressure Switch.

Common HVAC Issues This Part Addresses

• Compressor cycling caused by a faulty pressure switch
• HVAC system shutdown from incorrect pressure signal input
• Intermittent A/C operation on Toyota, Lexus, and Mitsubishi vehicles
• Pressure-related compressor protection faults
• Connector or terminal wear at the original switch location

Installation Notes and Tips

Verify the connector shape, terminal count, and M11 x 1.00 thread size before installation. This switch is system mounted and uses an open binary configuration, so confirm the vehicle’s HVAC setup matches the listed fitment, especially on Lexus GX460 models with rear A/C or dual-zone climate control. Always compare the original part number and connector style before service.

Quality Assurance

Four Seasons 20929 is engineered to meet or exceed OEM requirements for pressure-switch replacement in supported HVAC systems. Its steel body and Weather Pack connector support dependable service in demanding underhood conditions.