Porsche 718 Boxster Radiator Fan Isn't Working

Diagnosing the Causes of a Non-Functional Radiator Fan in Your Porsche 718 Boxster and How to Fix It

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Reviewed by
Bo Fader
Written by RepairPal Car Genius
Updated January 14, 2025
0%
34% chance it's the
Fan Motor or Clutch
0%
28% chance it's the
Fan Relay or Fuse
0%
23% chance it's the
Temp Sensor or Fan Control Module
0%
15% chance it's
Something else
The most common reasons a Porsche 718 Boxster radiator fan isn't working are the fan assembly, the fan clutch, or the coolant temperature sensor.
  • Fan Motor or Clutch: A faulty fan motor or a malfunctioning fan clutch can result in inadequate cooling, causing the engine to overheat.
  • Fan Relay or Fuse: A faulty fan relay or blown fuse can prevent the cooling fan from operating, leading to engine overheating.
  • Temp Sensor or Fan Control Module: A faulty temperature sensor or fan control module can result in incorrect readings, causing the engine to overheat or the cooling fan to operate improperly.
Proper diagnosis will determine the exact cause of your symptom, saving you money on unnecessary repairs. The diagnostic experts at RepairPal Certified shops have the right tools and experience to solve any symptom.

How much does it cost to fix a Porsche 718 Boxster radiator fan isn't working?

Common Repairs

The total repair cost will vary based on the condition of your vehicle and the number of repairs needed to fix your symptom. Proper diagnosis will save you money by finding the exact repairs needed to fix your car right the first time.

Over time serpentine belts stretch, crack, and the ribs that ride on the accessory pulleys being to wear smooth. A squealing noise that increases with engine speed or as engine driven accessories are turned on may be noted. The noise is caused by the belt slipping on the pulleys, insufficiently driving them. Ineffective air conditioning, a battery warning light, or intermittent power steering assist can result from this.

»MORE: Symptoms of a bad serpentine belt

The bad thermostat can cause two different sets of problems, depending on whether it's stuck open or stuck closed.

A thermostat that is stuck open can cause the engine to run colder than normal and turn on the check engine light. It may also cause poor fuel mileage and the heater to blow cool air.

A thermostat that is stuck closed will cause the vehicle to overheat. If a new thermostat doesn't resolve engine temperature problems, the cooling system needs to be checked for other issues.

» LEARN MORE: Signs of a bad thermostat, and how to fix it

When the engine coolant temperature sensor fails, it will send inaccurate information to the vehicle’s computer, causing the computer to react to false operating conditions. This will cause the engine to consume more fuel than normal, depleting fuel mileage, and causing black, sooty smoke from the engine under moderate to heavy acceleration. The check engine light will illuminate, and on-board diagnostic trouble codes may be stored for exhaust and emission system failure, fuel delivery system failure, and engine cooling system failure. Overheating may also occur, as the coolant sensor may be leaking fluid out of the engine, creating a an air pocket in the system.

When the radiator fans stop functioning properly, the engine temperature will rise. The spike in temperature will be highest when the vehicle is idling at a stop, but should subside once the vehicle begins moving again.

Additionally, the air conditioner typically won't blow as cold. This is because the air from the radiator fans also blows across the air conditioning condenser, so when the fans fail, both systems suffer.

You'll also usually see the check engine light and notice a drop in fuel economy. It's possible the fan will start making noise if it's failing, as well.

Troubleshooting Radiator Fan Issues in a Porsche 718 Boxster

When troubleshooting radiator fan issues in your Porsche 718 Boxster, it's essential to adopt a systematic diagnostic approach. Start by examining the fan assembly to confirm it operates correctly, as this is the most straightforward component to check. Next, inspect the fan motor or clutch for any signs of malfunction, as these parts are critical for fan operation. Following this, verify the condition of the fan relay and fuse, as these electrical components can often be the source of the problem. The coolant temperature sensor is another vital element; ensure it is functioning properly, as it directly influences the fan's activation. If the fan still does not operate as expected, consider the fan control module, which may require further investigation. For a more in-depth analysis, testing the relays using a jumper or a diagnostic tool like Durametric can provide additional insights. Pay attention to any unusual fan behavior, such as excessive running speeds, which may indicate underlying issues with the temperature sensor or other related components. By methodically checking these elements, you can effectively identify and resolve the radiator fan issues in your Porsche 718 Boxster, ensuring optimal performance and reliability.

What to Check When the Radiator Fan Isn't Working in a Porsche 718 Boxster?

When diagnosing why the radiator fan isn't functioning in your Porsche 718 Boxster, it's essential to systematically check several critical components. Start with the fan assembly itself, as a malfunction here is a frequent culprit. Next, inspect the fan clutch, which can prevent the fan from engaging properly. The coolant temperature sensor is another vital part to examine, as it plays a crucial role in signaling when the fan should activate. Additionally, consider the fan motor or clutch, as issues in these areas can directly affect performance. Don't overlook the fan relay or fuse, as a blown fuse or faulty relay can disrupt the electrical flow necessary for the fan to operate. Lastly, the temperature sensor or fan control module may also be at fault, so ensure these components are functioning correctly. By methodically checking these elements, you can effectively troubleshoot the radiator fan issue and potentially resolve it without professional assistance.

Why is the Radiator Fan Not Working in a Porsche 718 Boxster?

When the radiator fan in your Porsche 718 Boxster fails to operate, it is crucial to address the issue promptly to avoid severe engine damage. The radiator fan plays a vital role in maintaining optimal engine temperatures by drawing air through the radiator, especially during low-speed driving or in heavy traffic. If the fan is not functioning, the engine may overheat, leading to costly repairs and potential safety hazards. Common culprits for a malfunctioning fan include the fan assembly, fan clutch, coolant temperature sensor, and various electrical components such as relays and fuses. Ignoring these symptoms can exacerbate the problem, resulting in more extensive damage to the engine and cooling system. Therefore, if you notice any signs of fan failure, such as unusual engine temperatures or the fan not engaging, it is essential to conduct a thorough diagnosis and repair as soon as possible to ensure the longevity and reliability of your vehicle.

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Porsche 718 Boxster Radiator Fan Not Working | RepairPal