Help. Can the anti theft blinking light drain my battery?

I’ve learned the blinking light of a car with a key in it is the anti theft. My battery was drained while I was on a long vacation and I’m wondering if the blinking light could have done it. Any info is helpful thanks

 

What’s a long vacation?

 

Doubtful, that security system doesn't draw much power. If your battery was dead it was likely just due to it sitting a while.
How long were you away?

 

Maybe if it was a turn signal blinking for a week but not a low power led. High power leds can consume whole amps while low power leds consume milliamps.

 

It comes back to how long you are away .

There are a few draws always when the battery is connected

 

Welcome to the forum. To answer your question, NO, it's highly unlikely that the anti theft will kill your battery.

 

While I would tend to agree with people who think that the blinking security light will not drain a battery, it is not helping your battery to stay alive. The current draw is small, but a draw, nonetheless.
If a real drain is suspected, I find the best way to locate it is to use the amp scale on a voltage ohm meter across all points in all of the fuse boxes. Fuses are removed one at a time, amp meter probes inserted. I usually wait about 1/2 an hr. to start the test. Gives the more active circuits some time to go to sleep. Those higher consumers may wake up when you hit them with the probes. A quick glance at the fuse diagram will identify that fuse - usually security related.