Why does my key keep flashing? It has run out of battery twice already.

[Noel]

Even though I am not the main user of the car, my wife is, my key has run out of battery twice and her’s never has in nearly 3 years. I notice that even inside the house my key, which I keep by the front door, has a flashing red light come on when it’s near the front door. Why? Is this causing the battery in the key to keep running out? Any ideas anyone?

[simonmaskell]

The key flashes when it is in proximity to the car. Having said that after a few minutes if not moved the key goes to sleep. This prevents wireless relay attacks. So if the key never stops flashing once it is still ( suggest you wait 10 minutes) then you may have a problem. I have only replaced the battery on the key that is consistently used once in 2.5 years.