2021 Battery Drain

Hey All,

Looking for advice...I bought my wife a 2021 Touring around 7 months ago; the car only had around 23k miles on it when I bought it and now has around 29k miles.

This past Friday, my wife found that the car battery was completely drained after sitting out overnight (car wouldn't start and key fob wouldn't unlock the car). She called AAA and had them replace the battery. She drove the car to work and then back home without issue.

On Saturday morning, the same issue occurred again: the battery was completely drained after sitting out overnight. AAA came out again and replaced the battery again (under warranty, just in case we got a bad battery). My wife and I then drove the car around 200 miles throughout the day on Saturday.

On Sunday afternoon (after the car sat for around 18 hours), the battery was drained again.

I took the car to the dealership this morning and they tested the battery and did a drain test (both of which came back normal). The only issue they could find was that the battery was harness was over tightened, so they suggested replacing the entire battery wire harness (quoted $411).

I asked the service center if this could be a DCM issue, which they said was unlikely as it would have come up on the drain test. I read one other person had an issue with the electronic parking brake getting stuck (causing a continuous trigger to the ECU). Are there any other potential issues that could be causing this (I checked the cargo area light, made sure nothing else is/was on).

This is my first Subaru, so not super familiar with the common issues.