What controls an electric fan clutch?

Electronic – Viscous EV Fan Clutch Operation This engagement process is ultimately controlled through the ECM/PCM by the following input variables: Coolant Temperature, Intake Manifold Temperature, Transmission Oil Temperature, A/C Pressure and Engine Oil Temperature.

How do you test a clutch fan solenoid?

An easy test for the function of the solenoid only is to start the truck, let it run and wait for the fan to disengage when air pressure builds to normal. If you then shut the truck off, which kills power to the solenoid, you should immediately hear the solenoid vent the air that is in the line going to the clutch.

What are the symptoms of a faulty fan clutch?

How to Tell If Your Fan Clutch Is Going Bad?

  • Vehicle overheating. An overheating engine is often the first symptom that is commonly associated with a bad or failing fan clutch.
  • Loose and Wobbling Fan.
  • Excessively loud cooling fans.
  • A decrease in acceleration, power & fuel efficiency.

How does a clutch fan know when to engage?

Thermal fan clutches use a bi-metallic spring to sense temperature. When the engine is cool, the fan is disengaged. As the temperature increases, the spring rotates the valve plate and allows the fluid to flow. This engages the fan.

What does a fan clutch solenoid do?

The clutch engages and makes the fan turn when the valve opens, sending air pressure to overcome a spring and push the Piston Friction Disc (PFD) against the friction material. It disengages when the valve closes, allowing the clutch solenoid to exhaust air and let the spring return.

Should a fan clutch spin freely when cold?

The Fan Can Move Freely When the clutch is cold, the fan can be moved by hand, but it cannot be spun up. There’s enough resistance in the system to allow you to move the fan, but keep it from spooling up when hit by air pressure.

What is a fan clutch solenoid?

The solenoid valve can be thought of as the “heart” of the control system, opening and closing to regulate airflow to the fan drive. The solenoid valve is a three-way valve with two inlet/exhaust ports and one outlet port.

At what temperature should a fan clutch kick in?

about 170°F
At what temperatures do fan clutches engage? Answer: Most fan clutches engage at about 170°F air temperature (about 180-190°F engine temperature).

How does an air operated fan clutch work?

A Fan Clutch engages the fan and makes it turn when the valve opens; it pushes the PFD (Piston Friction Disc) against the friction material and also sends air pressure to overcome a spring. It disengages when the valve is closed, which allows the solenoid to exhaust air and let the spring return.

What is fan drive?

Fan Drive (or Fan Clutch) The purpose of a fan clutch with a mounted fan is to help ensure that engines do not exceed certain operating temperatures, which are usually set by the manufacturer. The temperature is detected by a bimetallic sensor system or by an electronic control.

What triggers the radiator fan?

On most modern cars, the cooling fan is controlled by the Engine Control Unit (ECU) which gets a signal from the coolant temperature sensor. If it’s not working, the fan won’t turn on when it needs to, which means the engine might overheat.