Standard Ignition AX329 HVAC Heater Core Temperature Sensor

HVAC Heater Core Temperature Sensor for Ford F-150

Standard Ignition AX329 is a direct-fit HVAC heater core temperature sensor built to replace a damaged OE unit and restore accurate coolant temperature signaling from the heater core. It is used with ambient air, sun load, and cabin temperature inputs to help the HVAC system manage heater and fan operation on Ford F-150 applications.

Compatible With 2004-2008 Ford F-150 and 2004 Ford F-150 Heritage, this sensor is built for service work that demands correct electrical performance and stable readings. The AX329 is also a fitment-based search match for technicians looking for a Ford F-150 heater core temperature sensor replacement.

Key Features

• Direct-fit replacement for the original heater core temperature sensor
• Female connector with rectangular plug-in design
• 2 blade terminals with male terminal gender
• High-temperature housing for harsh engine bay conditions
• Supports accurate HVAC temperature signal input for heater and fan control
• Built with durable materials for long service life

Detailed Description

Standard Ignition AX329 is engineered as an OE-style replacement for the heater core temperature sensor used in HVAC control systems. By relaying coolant temperature information from the heater core, it helps the vehicle’s climate control logic process inputs from the ambient air, sun load, and cabin temperature sensors. That signal coordination is important for consistent heater output and fan operation in Ford F-150 and Ford F-150 Heritage applications.

This part cross-references 4L3Z19C734AA and 72-4814 for the same application. The AX329 part number is commonly searched by buyers needing a Ford F-150 HVAC heater core temperature sensor replacement that matches the original connector style and electrical interface.

Common Issues This Sensor May Address

• Incorrect heater output temperature
• HVAC fan behavior that does not match cabin demand
• Faulty or inconsistent coolant temperature signal from the heater core
• Climate control readings that do not respond correctly to sensor inputs
• Replacement of a damaged or failed OE heater core temperature sensor

Installation Notes and Tips

Verify connector shape, terminal count, and sensor location before installation. The AX329 uses a female rectangular plug-in connector with two blade terminals, so the harness should match the original configuration on the vehicle. Confirm fitment for 2004-2008 Ford F-150 and 2004 Ford F-150 Heritage before service, and inspect the surrounding HVAC components for heat damage or corrosion that could affect sensor performance.

Quality Assurance

Standard Ignition builds this sensor with high-temperature housing and robust materials to meet the demands of professional repair work. The design focuses on electrical reliability and long service life in demanding engine conditions.