1991 Mazda B2600 Radiator Fan Isn't Working

Diagnosing the Causes of a Non-Functional Radiator Fan in Your 1991 Mazda B2600 and How to Fix It

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Reviewed by
Devin Cabugcal
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 1991 Mazda B2600 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 1991 Mazda B2600 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 first indication of a defective fan clutch is a healthy cooling system that runs below or above the normal temperature range. This is due to the fan running too fast or too slow. Also, a seized cooling fan will cause a loud roaring fan noise from under the hood every time the accelerator is pressed, and the engine will feel as if it lacks power. In this situation it would be very difficult to turn the engine cooling fan by hand, of course when the vehicle is off. Finally, if the clutch fails the fan will either turn very slowly, and not respond well to engine speed.

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 steps should I take to diagnose the non-functioning radiator fan in my 1991 Mazda B2600?

To effectively diagnose the non-functioning radiator fan in your 1991 Mazda B2600, begin with a systematic approach that prioritizes simpler checks before delving into more complex issues. Start by inspecting the fuse associated with the radiator fan; a blown fuse is a common and easily fixable problem that can halt fan operation. If the fuse is intact, proceed to examine the relay, as it plays a crucial role in supplying power to the fan. A malfunctioning relay may require replacement. Next, test the fan motor directly by applying power to it; if it fails to operate, the motor itself may need to be replaced. Additionally, check the temperature sensor, which is responsible for signaling the fan to activate when the engine reaches a certain temperature. A faulty sensor can prevent the fan from turning on. Don’t overlook the wiring and connections; ensure there are no loose or damaged wires that could disrupt power flow. Lastly, verify the coolant levels, as low coolant can also affect fan functionality. By following this diagnostic approach, you can efficiently identify and resolve the issue with your radiator fan.

What are the common causes for the radiator fan not working in a 1991 Mazda B2600?

When dealing with a non-functioning radiator fan in a 1991 Mazda B2600, it's crucial to understand the common problems that could be at play. One of the primary culprits is a faulty fan motor, which can fail to spin and thus prevent adequate engine cooling. Additionally, a blown fuse in the fan circuit can interrupt the power supply, rendering the fan inoperative. Another potential issue is a defective temperature sensor, which may fail to signal the fan to activate when the engine reaches its optimal temperature. Furthermore, a broken or slipping fan belt can hinder the fan's ability to spin effectively, leading to overheating. Lastly, a coolant leak can result in insufficient coolant levels, causing the engine to overheat and the fan to stop working due to inadequate coolant circulation. By diagnosing these common issues, DIYers can effectively troubleshoot and repair the radiator fan, ensuring the engine remains cool and functional.

How urgent is it to repair the non-working radiator fan in a 1991 Mazda B2600 to prevent engine overheating?

Repairing a non-working radiator fan in a 1991 Mazda B2600 is an urgent matter that should not be overlooked. The radiator fan is essential for maintaining optimal engine temperature by effectively dissipating heat from the radiator. When this component fails, the engine is at risk of overheating, which can lead to severe damage, including blown head gaskets and damaged pistons. Such repairs can be financially burdensome and may even result in complete engine failure if the problem is not addressed swiftly. Additionally, an overheating engine can compromise vehicle performance, leading to increased fuel consumption and potential safety hazards, such as unexpected breakdowns. Therefore, it is crucial for DIY enthusiasts to prioritize the repair of the radiator fan to ensure the vehicle operates safely and efficiently, ultimately prolonging its lifespan and preventing costly repairs down the line.

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