Battery drains while plugged in

[Carbonfiber]

Battery has been acting weird lately. Now I’m dealing with the battery draining while the car is still plugged in. It’s been minimal, 1-3%. Never experienced this before though. It’s not set on a schedule. Ironically, when I check the energy app, I see that I lose about 1% from mobile and 2% from standby. It also tells me that I should keep my car plugged in to prevent battery lost. My car is plugged in! Lol

I don’t get it.

 

[jcanoe]

The standby energy usage is likely caused by having Sentry Mode active at your Home location. This prevents the Tesla Model Y from entering Sleep mode. Also, if you have purchased Full Self Driving (FSD) the Summon Standby mode will prevent the Tesla Model Y from entering Sleep mode.

You can set Sentry Mode to be OFF at your Home location, turn off Summon Standby.

In colder temperatures the Tesla Model Y can show a slightly reduced battery capacity. This winter I have observed 3% lower battery than expected, especially just after having completed charging.

 

[Carbonfiber]

Forgot to mention sentry and cabin overheat protection are off

 

[jcanoe]

Forgot to ask, do you have any third party energy monitoring apps installed that have access to your Tesla account credentials? These apps may behave in unexpected ways, keep the Tesla vehicle from entering sleep mode. Sometimes, after a Tesla software update, the updated Tesla code affects the way a third part app interacts with the Tesla vehicle.

 

[Carbonfiber]

Forgot to ask, do you have any third party energy monitoring apps installed that have access to your Tesla account credentials? These apps may behave in unexpected ways, keep the Tesla vehicle from entering sleep mode. Sometimes, after a Tesla software update, the updated Tesla code affects the way a third part app interacts with the Tesla vehicle.

No third party apps

 

[jcanoe]

If your Tesla Model Y has the 12V lead-acid starting battery the Tesla Model Y may be having to wake up, charge the 12V battery more frequently as the 12V battery may not be holding a charge as well as when new. There are BT battery monitors you can install that will provide information on the state of the voltage of the 12V battery. (I just tested the 12V battery in my 2020 LRMY and it tested good, so I will test it again in 6 months.)

Other possibilities include a parasitic drain of unknown source and the cold tax that Tesla seems to be applying to the battery state of charge and range estimate in the latest software releases.

 

[SkyDog]

Did the outside temperature drop? That could account for seeing the battery estimated % drop a couple of points. Even while plugged in, it wouldn't automatically start recharging again until it dropped something like 5% (I think).

 

[ElMostrito]

Makes zero sense for there to be phantom draining while the vehicle is powered in to an unlimited power source. This un necessarily degrades the battery.

 

[Benito1283]

Makes zero sense for there to be phantom draining while the vehicle is powered in to an unlimited power source. This un necessarily degrades the battery.

The battery is likely not actually draining. Often when parked the battery will recalibrate/recalculate its capacity after some time and it will be a little higher or lower, often depending on outside temp. Wouldn’t worry about it.

I agree that the blurb on the energy screen about keeping the car plugged in to reduce drain is misleading.

 

[ucmndd]

Makes zero sense for there to be phantom draining while the vehicle is powered in to an unlimited power source. This un necessarily degrades the battery.

It makes perfect sense. Even when plugged in, the car doesn’t stay “on” constantly powering the charging circuitry to draw energy from the wall.

The car will allow the main battery to discharge about ~3% before it schedules or initiates a top-up charge from the wall power.

 

[flixden]

The battery is likely not actually draining. Often when parked the battery will recalibrate/recalculate its capacity after some time and it will be a little higher or lower, often depending on outside temp. Wouldn’t worry about it.

I agree that the blurb on the energy screen about keeping the car plugged in to reduce drain is misleading.

I am 99.9% sure that the battery will drain, down to a roughly 3% "loss", then the car will top it back off. Then the cycle repeats.

 

[Benito1283]

I am 99.9% sure that the battery will drain, down to a roughly 3% "loss", then the car will top it back off. Then the cycle repeats.

Right. It doesn’t actually “prevent” drain, it just restores it when it crosses a certain threshold.

 

[Vicj]

Right. This is simply about the battery management software balancing cells. There will often be a very small drop, or gain, in total capacity when it does this after sleeping. It's nothing to be alarmed about at all .
The other thing to watch, especially for new owners, is to limit the number of times you open your Tesla app. When you do, and the app connects with the car, your car will "wake up" from sleeping, and use a small amount of power. Just let it sleep.
Even just being NEAR your car with your phone in your pocket abs your Bluetooth on will wake it up. I do a lot of projects in my garage, and even if I park the Tesla outside, if I forget to turn off the Bluetooth, I'll hear the climate control running in the car.
So it doesn't take much to wake the car up.

 

[ucmndd]

I do a lot of projects in my garage, and even if I park the Tesla outside, if I forget to turn off the Bluetooth, I'll hear the climate control running in the car.

This should never happen as a result of being near the car or waking it up. Whatever you’re hearing is not the climate control running in the cabin.

 

[Vicj]

I'm pretty certain it is. But even if I'm wrong, the car is certainly awake, just from being near the phone

 

[ucmndd]

I'm pretty certain it is. But even if I'm wrong, the car is certainly awake, just from being near the phone

What possible reason would your car have to be conditioning the interior because your phone is near?

 

[Vicj]

No idea. But it's waking up, turning on, and the climate control starts. We shouldn't be hijacking this thread with this. Even if I'm completely wrong, and it's done OTHER system coming on and blowing air, the fact is the car wakes up when the phone is near.