Buy Subaru Legacy Auxiliary Engine Cooling Fan Relays

The auxiliary engine cooling fan relay is an essential component of a vehicle's cooling system. It controls the operation of the secondary cooling fan, which helps regulate engine temperature under demanding conditions. By managing the auxiliary radiator fan, the relay ensures that the engine remains within optimal temperature ranges, preventing overheating and maintaining performance.

The primary role of the auxiliary cooling fan relay is to activate the secondary cooling fan when additional airflow is needed. This typically occurs during high-temperature situations, heavy engine loads, or when the air conditioning system is in use. The relay receives signals from the engine control unit (ECU) or temperature sensors and closes the circuit to power the fan. Proper operation of this relay is crucial for engine efficiency and longevity.

A faulty auxiliary engine cooling fan relay can lead to several noticeable issues:

Engine Overheating: If the relay fails, the auxiliary fan may not turn on, causing the engine to run hotter than normal.
Non-Operational Cooling Fan: The secondary cooling fan does not engage when expected.
Reduced Air Conditioning Performance: Ineffective cooling since the auxiliary fan aids the A/C system.
Illuminated Warning Lights: The check engine light or temperature warning indicator may appear on the dashboard.
Unusual Noises: Clicking sounds from the relay area due to intermittent relay operation.

To determine if the auxiliary cooling fan relay is malfunctioning:

Visual Inspection: Check for signs of corrosion, damage, or loose connections at the relay terminals.
Relay Testing: Use a multimeter to test the relay’s continuity and switching function.
Swap Test: Replace the suspect relay with a similar known-good relay to see if the problem resolves.
Check for Power: Verify that voltage is reaching the relay and that the ground connections are secure.
Consult Diagnostic Codes: Use an OBD-II scanner to identify any error codes related to the cooling system.

Replace with Quality Parts: Use reliable, high-quality relays designed for your specific vehicle model.
Follow Manufacturer Guidelines: Adhere to the vehicle manufacturer's instructions for relay replacement.
Disconnect Battery: Always disconnect the battery before replacing electrical components to prevent shorts.
Inspect Related Components: Check the cooling fan motor and wiring harness for any signs of wear or damage.
Regular Maintenance: Include the cooling system in routine vehicle inspections to catch issues early.

Replacing a faulty auxiliary radiator fan relay promptly is vital because:

Prevents Engine Damage: Overheating can cause significant engine problems, including warped heads or blown head gaskets.
Maintains Performance: Ensures that the engine operates efficiently, providing optimal power and fuel economy.
Enhances Comfort: Keeps the air conditioning system functioning effectively for passenger comfort.
Safety: Reduces the risk of unexpected breakdowns due to overheating.

Secondary Cooling Fan Relay
Auxiliary Radiator Fan Relay
Engine Cooling Fan Control Relay
Auxiliary Cooling Fan Switch
Cooling System Relay