2018 INFINITI Q70L Radiator Fan Isn't Working

Diagnosing the Causes of a Non-Functional Radiator Fan in Your 2018 INFINITI Q70L 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 2018 INFINITI Q70L 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 2018 INFINITI Q70L 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.

What steps should I take to diagnose the non-functioning radiator fan in my 2018 INFINITI Q70L?

To effectively diagnose the non-functioning radiator fan in your 2018 INFINITI Q70L, begin with the simplest solutions before progressing to more complex diagnostics. Start 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, inspect the relay, which controls the power supply to the fan; a malfunctioning relay may need replacement. Next, test the fan motor directly by applying power to it; if it fails to operate, the motor itself may require replacement. Additionally, examine the temperature sensor, as a faulty sensor can prevent the fan from activating when the engine reaches the necessary temperature. Lastly, inspect the wiring for any signs of damage or loose connections, as these can disrupt the power flow to the fan. If these steps do not resolve the issue, consulting a mechanic or dealership for professional assistance is advisable. By following this structured approach, you can efficiently identify and address the problem with your radiator fan.

What are the common causes for the radiator fan not working in a 2018 INFINITI Q70L?

When troubleshooting the radiator fan issue in a 2018 INFINITI Q70L, it's essential to consider several common problems that could be at play. A faulty fan motor is often the primary culprit, as it can fail to operate altogether, necessitating a replacement to restore functionality. Additionally, a blown fuse can interrupt the electrical flow to the fan, so checking the fuse box for any blown fuses is a crucial step in your diagnosis. Another potential issue is a malfunctioning temperature sensor, which may fail to signal the fan to activate when the engine reaches a certain temperature; replacing this sensor can often resolve the problem. Wiring issues, such as damaged or loose connections, can also prevent the fan from working properly, so inspecting the wiring for any visible damage is advisable. Lastly, ensure that the coolant level is adequate, as low coolant can lead to overheating and may cause the radiator fan to stop functioning. By systematically addressing these common causes, you can effectively troubleshoot and potentially fix the radiator fan issue in your vehicle.

How urgent is it to address the non-functioning radiator fan in a 2018 INFINITI Q70L?

Addressing a non-functioning radiator fan in your 2018 INFINITI Q70L is not just a matter of convenience; it is a critical safety concern that demands immediate attention. The radiator fan is essential for regulating engine temperature, and when it fails, the risk of overheating escalates significantly. Overheating can lead to severe engine damage, resulting in costly repairs or even complete engine failure. Moreover, a malfunctioning fan can compromise your vehicle's performance, leading to decreased fuel efficiency and potential breakdowns on the road. Ignoring these symptoms can create a cascading effect of mechanical failures, making it imperative to diagnose and fix the issue as soon as possible. By prioritizing the repair of your radiator fan, you not only safeguard your engine's health but also enhance your vehicle's overall reliability and performance.

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2018 INFINITI Q70L Radiator Fan Not Working | RepairPal