Fan Question

[Dino44]

Hello all,
I am new to this forum and a new porsche owner, so bear with me if I am a little ignorant.
My question is-
There is a fan that turns on when the car is off-I believe this is a secondary cooling fan of some sort? The fan will turn off and on every 20 seconds or so while the car is running-is this normal? It seems that by turning off and on so much that it would burn something out.
Any suggestions or comments on this would be appreciated.
Thanks,
Greg

It is a 1994 911 Carrera 2

[lucittm]

There are likely seven fans in your car. You can help us out if you could identify if the fan that is cycling is in the front of the car or in the back and also if the sound is more obvious inside the car or outside.

Thanks,
Mark

[Dino44]

The fan is making noise in the front of the car and it is louder when you are outside of the vehicle. I hope that narrows it down, I was unaware of the total number of fans. Thanks for your help.
Greg

[lucittm]

You have a large fan in each of your front fenders. In the driver's side, it belongs to the A/C condenser. Normally this fan (powered by Relay 14) only runs when the engine is running, the A/C is on, and the airflow across the condenser is not sufficient based on a temperature controller in the dash-mounted control unit. The other fan is in the passenger side fender and it belongs to the oil cooler. This fan (powered by Relay 4) is controlled by a variable temperature sensor on the oil cooler piping. The dash-mounted control unit also determines if the fan is needed and will cause the blower to run at low speed or high speed depending on the temperature. If the temperature is close to the switch limits, the fan will cycle on and off. However, I would check to see if the temps are too high, the fan should not run after the engine is off.

If you want to determine which fan it is, pull Relay 4 or Relay 14 while the fan is running and if it suddenly stops, you will know what circuit is involved.

Good Luck,
Mark