Dorman 904-618 HVAC Pressure Switch

Dorman 904-618 A/C Pressure Switch

Dorman 904-618 is a direct replacement HVAC pressure switch for R134A air conditioning systems. It is built for specific-fit applications and addresses common A/C failures caused by corroded terminals or a damaged connector at the original switch.

Key Features

• Direct replacement A/C transducer switch for restoring air conditioning function
• Specific fit for select Ford, Mazda, Lincoln, and Mercury vehicles
• 12-volt electrical design with 2-pin male terminals and female connector
• Black round connector with metal housing and bolt-on mount type
• Pressure limits: closed at 260 and open at 475
• Rated for R134A refrigerant systems
• Maximum pressure reading: 1250 PSI
• Thread diameter: 10 mm

Detailed Description

This HVAC pressure switch is used to monitor refrigerant pressure and help the A/C system operate within the proper range. Dorman 904-618 is a specific-fit replacement for many Ford Ranger, Ford F-150, Ford Explorer, Mazda B-series trucks, and related applications, making it a practical choice when the original switch has failed due to connector damage or terminal corrosion. This part cross-references Four Seasons 20916 and Standard Ignition PCS124 for the same application.

What It Helps Fix

• A/C compressor not engaging because of a failed pressure switch
• Intermittent air conditioning operation from corroded terminals
• Broken or damaged original switch connector
• Incorrect refrigerant pressure signal in the HVAC circuit
• Loss of cooling performance in R134A-equipped systems

Installation Notes and Tips

Verify the connector shape, terminal count, thread diameter, and refrigerant type before installation. This switch uses a bolt-on mount and a 10 mm thread diameter, with no mounting bracket included. Confirm the vehicle’s HVAC system uses R134A and match the original electrical connection before replacing the part. Fits 1994-2004 Ford F-150, N/A; Fits 1994-2004 Ford F-350, N/A; Fits 1994-2004 Mazda B3000, N/A; Fits 1998-2002 Lincoln Navigator, N/A.

Quality Assurance

Dorman replacement parts are engineered as direct-fit service components for restoring original system operation. Part number 904-618 is built to match the listed application requirements for select Ford, Mazda, Lincoln, and Mercury vehicles.