Chrysler 300 A/C Evaporator Temperature Sensor Guide for 2005-2019 Models
If your Chrysler 300's air conditioning is blowing warm or acting erratically, this small sensor could be the problem.
- A common symptom of failure is A/C air that cycles between cold and warm.
- A faulty sensor can trigger the Check Engine Light with code P0539.
- Replacement is a simple, low-cost DIY job accessible from the passenger footwell.
- Using an aftermarket sensor is a low-risk, high-value option for this specific repair.
Is Your Chrysler 300 A/C Acting Up?
When the air conditioning in your 2005-2019 Chrysler 300 isn't working right, many people assume it needs an expensive compressor or a refrigerant recharge. However, a common and much cheaper culprit is a faulty A/C evaporator temperature sensor. This sensor tells your A/C system when to cool down and when to take a break. When it fails, the whole system can get confused, leading to poor performance.
Common Symptoms of a Bad A/C Evap Temp Sensor
A failing sensor will usually produce a few distinct symptoms. Watch out for these signs in your Chrysler 300:
- Fluctuating Air Temperature: The most common sign is air from the vents that cycles between cold and lukewarm. The system can't get a steady temperature reading, causing it to work erratically.
- A/C Blows Warm Air: The sensor might fail in a way that tells the computer the evaporator is already freezing cold, even when it's not. This can prevent the A/C compressor from turning on at all, resulting in no cold air.
- Compressor Constantly Cycling: You might hear the A/C compressor clutch clicking on and off more frequently than usual as it tries to regulate the temperature based on bad information.
- Check Engine Light: A failure in the sensor's circuit can trigger a check engine light. You may find diagnostic trouble code (DTC) P0539, which points to an intermittent signal from the sensor. 🎬 Watch this quick guide to understanding the P0539 engine code.
Don't Mistake It for Other Problems
These symptoms can sometimes be confused with low refrigerant levels or a failing blend door actuator. However, the key indicator for the sensor is often the erratic temperature fluctuation. 🎬 See how to test and diagnose a faulty evaporator sensor. If you have access to an OBD-II scanner, checking for code P0539 is a strong confirmation.
Choosing an Aftermarket Replacement Part
For a simple electronic part like an A/C evaporator temperature sensor, an aftermarket replacement is a smart choice for most Chrysler 300 owners. The original Mopar part can cost more than double the price of an aftermarket version.
Since the labor to replace this sensor is minimal, the financial risk of using an aftermarket part is low. Unlike a major component buried deep in the dashboard, if an aftermarket sensor were to fail prematurely, replacing it again is not a difficult or expensive job. Aftermarket brands like Replacement offer a cost-effective solution that restores function without the high cost of an OEM part.
Cost Comparison: Chrysler 300 A/C Evap Temp Sensor
| Part Type | Estimated Cost |
|---|---|
| New Aftermarket | $21.77 |
| New OEM (Mopar) | $50 - $60 |
| Shop Labor | $49 - $72 |
DIY Installation Tip
The A/C evaporator temperature sensor is usually located in the passenger footwell, pushed into the side of the HVAC (heater) box. You will likely need to remove the panel under the glove box for access. The sensor itself is often held in by a single fastener or clip. While the space is tight, this is a job most DIYers can handle in under an hour with basic tools.
🎬 Watch this video for a step-by-step sensor replacement walkthrough.Frequently Asked Questions
Can I still drive my Chrysler 300 with a bad evap temp sensor?
Yes, you can. A bad A/C evaporator temperature sensor does not affect the engine's operation or the vehicle's safety. Your only issue will be poor or non-functional air conditioning, which can be uncomfortable in hot weather.
Is a refrigerant recharge needed when replacing this sensor?
No. The A/C evaporator temperature sensor is an external electronic part. Replacing it does not open the sealed refrigerant system, so no evacuation or recharge is necessary.
Are there any recalls for this part on the Chrysler 300?
No, there are no active recalls from the NHTSA for the A/C evaporator temperature sensor on 2005-2019 Chrysler 300 models. While there are recalls for other items like airbags, this specific part is not included.
What is the difference between the evaporator sensor and the ambient air temp sensor?
The evaporator temperature sensor measures the temperature inside your HVAC unit to prevent freezing. The ambient air temperature sensor measures the outside air temperature, and this information is usually displayed on your dashboard or used by the automatic climate control system to help regulate cabin temperature.
Helpful Videos
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Technical Specifications
OEM Part Numbers: 5143124AA
This is a two-wire thermistor-type sensor that plugs into the HVAC housing. Its electrical resistance changes with temperature, sending a variable voltage signal to the climate control module.
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Chrysler 300: