Description TEMPERATURE SENSOR Part Number: F140401C Direct replacement (cross ref) for 140401. Product Overview This aftermarket temperature sensor monitors engine temperature and sends that information to the vehicle’s monitoring system. It’s a small part, but it plays an important role in keeping the engine operating within a safe temperature range. Modern trucks rely on accurate temperature readings to manage engine performance and protect against overheating. When a temperature sensor begins to fail or send incorrect signals, it can trigger warning lights, inaccurate gauge readings, or even affect engine operation. Replacing a faulty sensor restores reliable temperature monitoring and prevents larger cooling system problems from going unnoticed. What the Temperature Sensor Does The temperature sensor measures the heat level within the engine’s cooling system, typically in the coolant passage or near the thermostat housing. It continuously reports that temperature to the truck’s electronic system, which then displays it on the dashboard gauge or sends alerts if temperatures rise too high. Accurate readings help the driver and the engine management system respond quickly to overheating conditions. If the coolant temperature climbs above normal levels, the driver can shut the truck down or investigate the cause before serious engine damage occurs. Common Problems This Part Solves Temperature sensors can fail over time due to heat exposure, electrical issues, corrosion, or internal wear. When the sensor begins to malfunction, drivers may notice fluctuating gauge readings, warning lights that appear without a clear cause, or temperature readings that seem unusually high or low. In some cases, a bad sensor can trigger engine fault codes or cause the system to misinterpret engine conditions. Why Replacement Matters A faulty temperature sensor doesn’t just affect the dashboard gauge. If the system is receiving incorrect information, the driver may not realize the engine is overheating until damage has already occurred. Compatibility and Fitment This aftermarket temperature sensor replaces OEM reference number 140401. It is designed to fit compatible applications requiring this sensor configuration. As with any engine sensor, verifying part numbers and vehicle specifications before installation ensures proper fit and operation. Installation and Service Notes Installation involves removing the old sensor from the cooling system port and installing the new sensor with the correct sealing method. During replacement, technicians inspect the wiring connector and surrounding area for other damaged wiring. While diagnosing cooling system issues, it is also a good idea to inspect the radiator mounting hardware such as the FK066228C radiator mount or F1303096 radiator mount, since loose mounts can cause vibration or stress on cooling components. Use Case Temperature sensors are commonly replaced during cooling system diagnostics, engine repair work, or when faulty readings appear on the dashboard. Many fleet maintenance programs keep sensors available to address temperature-related warning codes quickly. About Us We’re a family-owned group of Peterbilt dealerships dedicated to getting you the parts you need quickly and affordably. Whether you’re looking for Paccar OEM parts, reliable aftermarket replacements, or popular upgrades like seats and filters, we make it easy to keep your truck running and on the road. If you don’t see what you need online, just give us a call or send an email — chances are we can get it. We pride ourselves on fast service, fair prices, and being a partner you can depend on when downtime isn’t an option. FAQs Q1: What happens if a temperature sensor fails? A: When a temperature sensor fails, the engine may display incorrect temperature readings or trigger warning lights. Q2: Can a bad temperature sensor cause overheating? A: The sensor itself usually doesn’t cause overheating, but it can prevent the driver from knowing the engine is running too hot. Q3: How can I tell if the sensor is bad? A: Common signs include erratic temperature gauge movement, warning lights without a clear cause, or engine diagnostic codes related to coolant temperature readings. Q4: Is replacing a temperature sensor difficult? A: In most cases the replacement is straightforward, but access can vary depending on the engine layout. Proper sealing and careful handling of the electrical connector are important to prevent leaks or signal issues. Q5: Should wiring be checked when replacing the sensor? A: Yes, corroded connectors or damaged wiring can cause the same symptoms as a failed sensor, so it’s good to inspect the connector and wiring during replacement.
