Refurbished battery

[tv1530]

Hi everyone. I have a 2021 model 3 standard range I bought brand new and the battery was faulty at 36k miles so under the warranty Tesla replaced with a refurbished one. Now I’m noticing my charge isn’t holding. I lost 30 something miles of range yesterday with my car parked at work for 8 hours. Today I lost 20 something miles leaving the car parked for 5 plus hours at work. Any thoughts? Did they give me a crap battery?

 

[shahryaran]

Hard reset and calibrate battery

 

[father_of_6]

I don't think losing charge while parked is an indication of battery fault. It's more likely a software issue or user configuration.

Sentry mode, smart summon, and cabin overheat protection can all cause this.

Additionally, sometimes software updates can cause issues that induce vampire drain... perhaps not allowing the car to go to sleep properly. Third-party software can also cause this, if you're using any.

 

[tv1530]

I don't think losing charge while parked is an indication of battery fault. It's more likely a software issue or user configuration.

Sentry mode, smart summon, and cabin overheat protection can all cause this.

Additionally, sometimes software updates can cause issues that induce vampire drain... perhaps not allowing the car to go to sleep properly. Third-party software can also cause this, if you're using any.

Thanks, I do live in SoCal and it’s been very hot here lately. I’m noticing I do have the cabin overheat protection on. You think that could be doing it? Sentry activation is minimal and no 3rd party software.

 

[Kimmi]

I also live in SoCal and can tell you when it gets hot my model three range goes away very quickly!

 

[father_of_6]

Sentry activation is minimal and no 3rd party software.

It's not about how many times sentry is triggered, it's the very act of it being on that keeps the computer running and the car from going to sleep. If I remember correctly, some users suggest it could use about 1% of your battery per hour to have it on.

Obviously since different models and trims have different battery sizes, that's just a ballpark.

You think that could be doing it?

The heat could definitely be a major contributing factor. If the A/C is kicking on every 15 minutes to keep the car cool, that's going to cause additional demand on your battery.

My recommendation is to test this yourself. One night before you go to sleep, turn off cabin overheat protection, sentry, and smart summon if you use it. Park in the garage if you have one. Don't plug the car in overnight, and note the state of charge before you go to sleep... then check the next morning to see if you lost anything. I bet there will be very little (if any) vampire drain. Don't forget to turn those things back on the next morning if you need them.

Parking in the shade is good for *every* vehicle if possible.

That's not to say vampire drain doesn't happen sometimes. There have definitely been cases where the software caused vampire drain, but Tesla fixes those things and you just have to wait for them to push those fixes.

I'm not an electrical engineer, but from reading in the forums it seems like failing batteries tend to appear as an inability to charge and/or an inability to drive at all... I don't recall drain being a symptom of battery failure - just a symptom that something is using the energy.