2017 Subaru Crosstrek dead battery?

[dhay13]

So we bought this car new and it now has 55,000 miles on it. Had to replace the original battery about a year ago. I bought a larger capacity battery as I always do. This morning she went out to start it and it was dead so she drove my truck. I work from home so went out and put the voltmeter on it and it read 3.8 V...ugh. Got in and the headlight switch was on. That's odd cause it has auto headlights and we never touch that switch. But my question is...on most newer cars don't the headlights turn off automatically after 5 minutes or something after you turn the car off? Like I said, we never touch that switch but I thought newer cars had this built in?
I charged the battery and it was at 13.0 when I disconnected it. Gonna let it sit a few hours then check again to be sure it's holding a charge.

 

[crash68]

Does this have a push button start and is it possible the vehicle was left in an Accessory On condition?
Maybe you had a freak battery failure, see if hold a charge connected to the car for 24 hrs.

 

[dhay13]

It's a push button start. don't think it was left in accessory on. To do that you need to keep your foot off the brake and hit the push button either once or twice, depending on what you are trying to activate. But if you are turning the car off then it can't be in accessory mode unless you hit the button more than once when you turn it off.
It may be a bad battery but this did happen before but it was the overhead map light last tie. That was likely user error. The headlights were the culprit this time as the switch is on the left side lever and it has to be twisted to get to the on position so that was definitely turned manually and not by accident. Just not sure why but obviously it happened. But I thought the headlights would turn off if left on by accident.

 

[crash68]

The headlights were the culprit this time as the switch is on the left side lever and it has to be twisted to get to the on position so that was definitely turned manually and not by accident. Just not sure why but obviously it happened. But I thought the headlights would turn off if left on by accident.

Usually if the headlights are left on with the ignition off/door open you'll get that annoying dinging from the car. You would think a '17 would turn the headlights off if left on, all the vehicles I've dealt with in the past 10 years have this feature (no Subarus though).

 

[dhay13]

Usually if the headlights are left on with the ignition off/door open you'll get that annoying dinging from the car. You would think a '17 would turn the headlights off if left on, all the vehicles I've dealt with in the past 10 years have this feature (no Subarus though).

That's what I thought. I disconnected the charger last night then checked the battery just before bed and it was at 13.0, same as it was a few hours earlier when I disconnected it. Started up fine this morning and she made it to work.