How does the cooling fan function?

[AlanS]

My wife's 2013 S60 had a dash display several weeks ago stating that the car was overheating...needed time to cool down. Since then, no return of the message, no codes on my scanner. Question: If I put on the A/C, the cooling fan will run. I seem to remember times when I would shut down the engine and the fan would continue to run. This hasn't happened lately....WHEN IS THE FAN SUPPOSED TO COME ON? How do I ( given limited electrical experience) find out if the fan is doing its job? Again, I haven't heard it come on recently....but it will come on with the A/C.

[scot850]

The engine cooling fans control modules are a weak point on these cars and prone to failure, as are the fan motors themselves.

They become intermittent causing overheating issues. If you are having issues I would be checking these over.

The issues can be caused by the following in the cooling sstem:

1) Thermostat - I just replaced one in a 06 P1 (V50) as it had failed shut and was causing overheating at idle or in traffic.
2) Coolant temperature sensor - These can fail or the wiring connections which operate the fan can become corroded causing lost signals to the fan motor to run.
3) Fan motor controller as mentioned.
4) Fan motor(s) - Some P3 cars have 2 fan motors.

Neil.