2017 Lexus GS450h Radiator Fan Isn't Working

Diagnosing the Causes of a Non-Functional Radiator Fan in Your 2017 Lexus GS450h and How to Fix It

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Reviewed by
Andrew Hajjar
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 2017 Lexus GS450h 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 2017 Lexus GS450h 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.

What are the initial diagnostic steps to take when the radiator fan isn't working on a 2017 Lexus GS450h?

When faced with a non-functioning radiator fan in your 2017 Lexus GS450h, it's essential to adopt a systematic diagnostic approach. Begin by checking the fuse associated with the radiator fan, as a blown fuse is a common and easily fixable issue that can halt fan operation. If the fuse is intact, the next step is to inspect the relay, which is responsible for supplying power to the fan; a malfunctioning relay can disrupt the entire system. Following this, test the fan motor itself to ensure it is receiving power; if it isn’t, you may need to investigate the wiring or consider the possibility of a faulty motor. Additionally, examine the cooling system for any coolant leaks, as low coolant levels can lead to overheating and may prevent the fan from activating. Lastly, verify the functionality of the temperature sensor, which is crucial for signaling the fan to turn on when needed. By methodically working through these steps, you can effectively diagnose and address the radiator fan issue in your Lexus, potentially saving time and repair costs.

What are the common causes for the radiator fan not working in a 2017 Lexus GS450h?

When troubleshooting the radiator fan in a 2017 Lexus GS450h, it's essential to consider several common problems that could be causing the fan to malfunction. A faulty fan motor is often the primary suspect, as it directly impacts the fan's ability to cool the radiator. Additionally, a blown fuse can interrupt the power supply to the fan, rendering it inoperative. It's also crucial to check the temperature sensor, as a malfunction here may prevent the fan from receiving the necessary signals to activate. Wiring issues, such as damaged or corroded connections, can disrupt the electrical flow to the fan, while low coolant levels can affect the fan's performance since it relies on coolant to regulate engine temperature. Lastly, a malfunctioning fan relay can prevent the fan from receiving power altogether. By systematically examining these potential issues, you can effectively diagnose and resolve the problem with your radiator fan.

How urgent is it to repair the non-working radiator fan in a 2017 Lexus GS450h to prevent engine overheating?

Repairing a non-working radiator fan in a 2017 Lexus GS450h is an urgent matter that should not be overlooked. The radiator fan is essential for regulating the engine's temperature by dissipating heat generated during operation. If the fan fails, the engine is at a significant risk of overheating, which can lead to severe consequences such as warped cylinder heads, blown head gaskets, or even complete engine failure. Additionally, overheating can trigger malfunctions in other engine components, resulting in costly repairs and extended downtime. Ignoring the symptoms of a faulty radiator fan can exacerbate the problem, placing undue stress on the entire cooling system and leading to further complications. Therefore, it is crucial for DIY enthusiasts to address any issues with the radiator fan promptly to ensure the vehicle's longevity and optimal performance, ultimately preventing expensive repairs in the future.

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