Inside the climate control module, there is a small fan that draws air from the car's interior and past a temperature sensor. The fan is active anytime the car is not "asleep" - the car wakes up when you open a door or unlock it with the key / it goes to sleep about 20 min after the key has been removed and no activity. When running properly, it is inaudible. The constant ticking noise tends to show up if the fan is dirty and/or off balance. The AC / Climate control module can be taken apart and the fan can be cleaned. With the faceplate off, you can stop the fan with your finger and the noise should go away - Stopping it will not hurt the fan's motor because the fan is magnetic and not directly connected to the motor.

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2005 X5 4.4L - 130K
- Premium Package
- Sport Package
- Rear Climate Package
- Cold Weather Package
- Multi-Contour Seats
- Heated Rear Seats
- Park Distance Control
- Navigation
- Premium HiFi w/CD Changer and Auxiliary Input