2015 GMC Terrain Radiator Fan Isn't Working

Diagnosing the Causes of a Non-Functioning Radiator Fan in Your 2015 GMC Terrain 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 2015 GMC Terrain 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 2015 GMC Terrain 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 steps to diagnose the non-functioning radiator fan in a 2015 GMC Terrain?

When diagnosing a non-functioning radiator fan in a 2015 GMC Terrain, it's crucial to follow a structured diagnostic approach that prioritizes simpler checks before delving into more complex issues. Begin by examining the fuse linked to the radiator fan, as a blown fuse is a frequent culprit that can easily be replaced. If the fuse is in good condition, proceed to inspect the relay responsible for controlling the fan; a malfunctioning relay can disrupt the electrical current needed for operation. Next, test the radiator fan motor itself to confirm its functionality, as a defective motor will necessitate replacement. Additionally, scrutinize the wiring connected to the fan for any signs of wear, damage, or loose connections, as these can impede power delivery. Lastly, utilizing a diagnostic scanner to retrieve any error codes related to the cooling system can help pinpoint the underlying issue. By systematically addressing these areas, you can effectively diagnose and resolve the problem with your radiator fan, ensuring optimal performance of your vehicle's cooling system.

What are the common problems that could cause the radiator fan to stop working in a 2015 GMC Terrain?

When troubleshooting a non-functioning radiator fan in a 2015 GMC Terrain, it's crucial to consider several common problems that could be at play. A faulty fan motor is often the primary suspect, as it can fail to spin, leading to overheating. Additionally, a blown fuse in the fan circuit can interrupt the power supply, rendering the fan inoperative. Inspecting the fan blades is also essential; any damage or breakage can hinder air circulation, exacerbating cooling issues. Furthermore, a defective temperature sensor may fail to signal the fan to activate, resulting in overheating without the fan's assistance. Lastly, wiring issues can disrupt the electrical connection, preventing the fan from receiving the necessary power to operate. Addressing these potential problems promptly is vital to maintaining the vehicle's cooling system and preventing engine damage.

How urgent is it to repair the non-working radiator fan in a 2015 GMC Terrain to avoid engine overheating?

When dealing with a non-working radiator fan in a 2015 GMC Terrain, the urgency of repair cannot be overstated. The radiator fan is essential for regulating the engine's temperature by dissipating heat generated during operation. If this component fails, the engine may not receive the necessary cooling, significantly increasing the risk of overheating. This overheating can lead to severe damage, including issues with the cylinder head gasket, pistons, and cylinders, which can result in costly repairs and extensive downtime. Moreover, an overheated engine may shut down unexpectedly, leaving you stranded and facing additional repair expenses. Ignoring the signs of a malfunctioning radiator fan not only jeopardizes the vehicle's performance but also poses safety risks. Therefore, it is crucial to address this issue promptly by consulting a qualified mechanic to ensure the cooling system operates effectively and to prevent any potential engine failures.

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