[Lifttillbig]

Hey guys,

just bought myself a 2015 435i Coupe. Everything is great, but every time I unlock the car after a while the alarm goes off for about 1-2 seconds (2 aggressive beeps) and that's it.
When I unlock the car soon after I locked it, it doesn't happen.

From what I read online it could be the hood switch, and I found this thread but can't locate the switch at my car.

I'm pretty new to all this, learned a ton in the past few weeks when searching for a car, but drove a 2006 Jetta before and never really cared much about the technical stuff, so pardon haha.

If anyone could tell me where to find the switch and/or has any other ideas about what could cause this, I'd greatly appreciate it.

Cheers!

Edit: it seems it is hood switch unrelated. Could it be the battery? Though I don't see any sign inside regarding battery and one of the mechanics I talked to told me the car would let me know if anything should be with the battery..

Any other ideas, anybody?

[visionaut]

The hood lock switch is located in the drivers-side hood latch.

It could be the car letting you know the alarm went off since you last locked it… but I think that sound is a more subtle beep…

[Lifttillbig]

Thanks a lot. Think I found it, but could you confirm this is the one?

And yeah, the alarm is short but pretty aggressive..

[visionaut]

Not sure, but don’t think so… See here…

[Lifttillbig]

You know what's weird, for some reason I can't find a single image or video on hood switch for the 4 series, and just saw in this article it mentions 1,3,5,7 series etc. but leaves out the 4-series, so I guess that is not a thing in the 4 series.

[Lifttillbig]

Could it be battery-related? Though I don't see any sign inside regarding battery and one of the mechanics I talked to told me the car would let me know if anything should be with the battery..

Any other ideas, anybody?

[Lifttillbig]

Well, nobody responded but I figured it out myself and fixed it, so thought I'd share here in case anyone else ever has the same problem.

It was the battery.

The car had been standing around for over half a year. Bought a battery meter on Amazon for $15 and tested it, gave me a 'medium' sigal and showed the battery was at 12.43V.
Bought a battery charger on Amazon for $30, took out the battery, charged it for a few hours until full, put back in and it everything is working as supposed to, no more alarm going off

[Ryanfknt]

Originally Posted by Lifttillbig

Well, nobody responded but I figured it out myself and fixed it, so thought I'd share here in case anyone else ever has the same problem.

It was the battery.

The car had been standing around for over half a year. Bought a battery meter on Amazon for $15 and tested it, gave me a 'medium' sigal and showed the battery was at 12.43V.
Bought a battery charger on Amazon for $30, took out the battery, charged it for a few hours until full, put back in and it everything is working as supposed to, no more alarm going off

Thanks for following up with the solution to your problem.

my 204 335i has been doing this ever since I woke up to a dead battery.. I jumped it and all is well besides an obnoxiously loud 2 second car alarm every time I unlock it now. Even if i unlock it by touching the door handle WOOWOO goes the car alarm.. it’s been an embarrassing week getting into my car 😂😂
I’m going to try your fix in the morning, thanks again.