Battery Charge loss

[Abbadon7]

Hi I have a 2018 Model S with 76,000 on it. I recently left on a trip and left my car unplugged in my friend's driveway with a 90% charge (200 miles). I planned to be gone for just over a month and in the past the battery has lost 1-2% of charge a day so this seemed plenty of charge. I occasionally checked in on the app and the battery was losing charge much more rapidly than usual so I had my friend charge the car on her house power a couple of times. I didn't check the car for 10 days during which time the battery went from a 45% charge (105 miles) to zero. The HV battery being at 0 also drained the 12v battery. During this time everything was turned off in the car - sentry mode, cabin heat mode, I didn't use the app to check the car, the ambient temperature was between 55-80º and the software is up to date.

I had the car towed to a Tesla dealership who initially told me that the battery would be replaced under warranty. They subsequently told me that there was nothing wrong with the battery and that this was normal for a 6yr old battery.

The warranty states that it covers a loss of battery retention over 30% or a failed fuel cell. The Tesla dealership told me neither of these apply and that they subsequently wouldn't replace the battery.

The battery continues to lose about 5% charge (10 miles) a day when idle. Has anyone else experienced this or have any suggestions how to proceed with Tesla to get the battery replaced?

 

[brainhouston]

5% loss per day is normal for 1st few days, then it should go into deeper sleep n lose 5% in 3-4 days
That's how my 2016 x behaves with 105k mi
Also checking app has no affect on my drain

It's possible ur 12v is old n keeps requesting hv to recharge it...

 

[Rocky_H]

5% loss per day is normal for 1st few days,

It shouldn't be that high even with EVERY kind of terrible battery draining thing on, like sentry. And @Abbadon7 said sentry and those other things were off.

It's possible ur 12v is old n keeps requesting hv to recharge it...

That's the one that might have some possibility to it. We've seen that several times here on the forum, where the car keeps pouring more energy into the 12V, which is losing it badly because it has gone bad, and then the car pours more in, etc. etc. That can drain the main pack pretty fast.

 

[brainhouston]

It shouldn't be that high even with EVERY kind of terrible battery draining thing on, like sentry.

maybe but i have nothing else to compare it to n my car is AP1
but it always drops that much initially n i don't find anything wrong with my car...