Hi everyone,

I recently bought a Mazda3 Sport Skyactiv 5-door, about a month ago. The previous owner was the first owner and took really good care of the car, so overall it’s in great condition.

But I’m having one really annoying issue: the security alarm keeps going off randomly, even when the car is locked and there’s no visible reason, and it’s embarrassing because it disturbs the neighborhood.

For now, as a temporary fix, I’ve been pulling out the horn fuse at night just to stop the alarm sound, but obviously this isn’t a long-term solution.

Has anyone dealt with this problem before?
What should I check first?
Is there anything I can do to fix it without spending a lot?

Any advice, common causes, or DIY checks would be really appreciated.


Thanks in advance!