Humming sound , might be from alarm

[cprogrammer]

Hi,
Urgently need your help. I've never heard the sound before, but today while activating my alarm with the keycode, it seems when I turn my car off there is a quiet humming noise. I'm afraid it might run up the battery. I dont know the source of this sound, I'm assuming its from the alarm since thats the only thing I did in the car. It's not too loud but you can hear it. Is this normal? After deactivating the alarm it still continues. My car isn't moving either.


Thankyou for reading.

 

[Kirby]

Does it sound like it is coming from under the hood? Does it continue for 2 or 3 seconds and then stop?

If so, mine does it too. I haven't looked into it or been worried about it. It sounds exactly like the fuel injection system on my Volvo, which I have heard while doing work on the Volvo engine. But maybe someone can confirm my assumption?

 

[cprogrammer]

Thanks for the reply. It stopped now, but at the time it continued for a minute or two. It sounded like it was coming from the alarm. Could have been the battery. I assumed it was normal since there are so many functions on the onboard computer I assumed the battery was just controlling all those.