Four Seasons 20944 A/C Trinary Switch

Four Seasons 20944 Trinary Pressure Switch

Four Seasons 20944 is a system-mounted A/C trinary pressure switch for automotive HVAC systems that use a 4-terminal, pin-style connection. It monitors refrigerant pressure and supports compressor and fan control in the A/C circuit, making it a direct-fit service part for a wide range of Honda, Mazda, Toyota, Acura, Lexus, and Pontiac applications.

Key Features

• Brand: Four Seasons Pressure Switch line
• Part number: 20944
• Type: A/C trinary switch with system-mounted design
• Voltage: 12V
• 4 terminals with male pin connector
• Male fitting with M11 x 1.00 thread size
• Steel construction
• Weather Pack: Yes
• Meets or exceeds OEM requirements
• Pressure operating points: low on 30 psi, medium on 220 psi, medium off 180 psi, high on 350 psi

Product Details

The Four Seasons Pressure Switch 20944 is built for A/C systems that rely on a trinary pressure switch to manage compressor engagement and fan operation based on refrigerant pressure. This style is commonly used in OE HVAC layouts across vehicles such as the Honda Odyssey, Mazda 3, Toyota Camry, Acura MDX, and Lexus LX470. The system-mounted design, male M11 x 1.00 fitting, and pin terminal layout support straightforward replacement when the original switch has failed or is no longer reading pressure correctly.

This part cross-references UAC SW4004C and Continental 50036 for the same application.

Vehicle Fitment

• Fits 2006-2014 Honda Ridgeline, N/A
• Fits 2011-2014 Mazda 2, N/A
• Fits 2007-2012 Mazda CX-9, N/A
• Fits 2004-2011 Mazda RX-8, N/A
• Fits 1999-2010 Honda Odyssey, N/A
• Fits 2006-2010 Mazda 5, N/A
• Fits 2004-2009 Mazda 3, N/A
• Fits 2009 Mazda 3 Sport, N/A
• Fits 2002-2008 Acura TL, N/A
• Fits 2008 Mazda CX-7, N/A; To 5/1/08
• Fits 2003-2008 Pontiac Vibe, N/A
• Fits 2002-2008 Toyota Corolla, N/A
• Fits 2003-2008 Toyota Matrix, N/A
• Fits 2002-2008 Toyota Solara, N/A
• Fits 2003-2007 Honda Accord, N/A
• Fits 1998-2007 Lexus LX470, N/A
• Fits 2007 Mazda CX-7, N/A
• Fits 1998-2007 Toyota Land Cruiser, N/A
• Fits 2004-2007 Toyota Sequoia, N/A; Rear A/C not included in this assembly.
• Fits 2001-2006 Acura MDX, N/A
• Fits 2002-2006 Toyota Camry, N/A
• Fits 2000-2005 Honda Insight, N/A
• Fits 2001-2005 Lexus IS300, N/A
• Fits 2000-2005 Toyota Celica, N/A
• Fits 2004-2005 Toyota MR2 Spyder, N/A
• Fits 2000-2004 Toyota Avalon, N/A
• Fits 2001-2004 Toyota Prius, N/A
• Fits 2001-2003 Acura CL, N/A
• Fits 2000-2003 Toyota Echo, N/A
• Fits 2001-2003 Toyota RAV4, N/A
• Fits 2001-2003 Toyota Sequoia, N/A
• Fits 1998-2003 Toyota Sienna, N/A; Tow package compatible
• Fits 1996-1997 Lexus LX450, N/A

Common Replacement Uses

• Restores A/C compressor pressure signal control
• Addresses compressor cycling caused by a failed pressure switch
• Supports condenser fan operation when pressure thresholds are reached
• Replaces a damaged or corroded system-mounted trinary switch
• Helps correct HVAC pressure-related fault conditions in OE-style systems

Installation Notes and Tips

Verify the connector style, terminal count, and M11 x 1.00 thread before installation. This switch is system mounted and uses a male fitting, so the original mounting location and refrigerant circuit layout should match the vehicle application. Confirm the vehicle build date where noted, such as the 2008 Mazda CX-7 through 5/1/08, and review HVAC routing on models with rear A/C or tow-package notes before replacement.

Quality Assurance

Four Seasons 20944 is listed as meeting or exceeding OEM requirements and is built with a steel housing and Weather Pack protection for service in automotive HVAC environments. The Four Seasons Pressure Switch line is used for OE-style replacement across a broad range of import applications, including Honda Odyssey, Mazda 3, and Toyota Camry platforms.