Does PCM control cooling fan?
The PCM controls fan operation; it uses the signal from the ECT or engine coolant temperature sensor. This sensor senses the temperature of the engine’s coolant and sends a variable voltage signal to the PCM. The PCM operates the fan motor through the engine’s cooling fan relay.
How do I know if my cooling fan module is bad?
Symptoms of a Cooling Fan Module Failure
- An overheating engine. When the cooling fan module fails completely, the cooling fans will not work at all.
- Cooling fans running non-stop.
- Poor circulation of fresh air in the cabin of the car.
What controls the cooling fan?
The fans are controlled either with a thermostatic switch or by the engine computer, and they turn on when the temperature of the coolant goes above a set point. They turn back off when the temperature drops below that point. This clutch is positioned at the hub of the fan, in the airflow coming through the radiator.
When should the radiator fan kick on?
Your radiator fan should kick in at about 200 degrees Fahrenheit. If you notice your vehicle is overheating or at the very least running hotter than it normally does, listen for the fan to see if you can hear it.
Why is the radiator fan not working on my Subaru Forester?
If your Forester has a bad engine temp sensor the radiator fan won’t know to come on, because the ECU won’t know how hot the engine is. You’ll need to locate and test the engine temp sensor. Depending on the model year and engine, the location varies. If it does end up being this sensor, they are very affordable.
What causes a Subaru engine to overheat while driving?
As with most vehicles, if a Subaru overheats while being driven at slow speeds, it’s likely a failure of the cooling fan to power up completely. With applications made abroad — including parts made by the Japanese automaker — the speed of the cooling fan is controlled by a pulse–modulated fan motor.
Where are the fan relays on a Subaru Outback?
There’s a pair of two-pin green connectors, B75 and B76, under the dash on the left (driver) side, closer to the center console, that are normally not connected. When they are connected, and the ignition is turned On (engine not started), the ECU should repeatedly cycle several relays and solenoids on and off, including the two fan relays.
What should I do if my Subaru engine wont cool down?
To prevent this from happening, have your technician inspect your vehicle and explain that the coolant sensor and thermostat are properly calibrated. Furthermore, warm up and cool down the engine to test the reliability of the thermostat and sensor, and to vent any air that might be stuck in the cooling system.