Investigating Unexpected Battery Drain While Idling - Consider Factors Such as Charge Level, Location & More

Investigating Unexpected Battery Drain While Idling - Consider Factors Such as Charge Level, Location & More
Energies | Free Full-Text | Degradation of Lithium-Ion Batteries in an Electric Transport Complex

It is surprising to find that a 4-day old BMW iX50 battery drops at least 5% every night while sitting outside in Maryland. This is similar to the Tesla vampire drain levels before 2018, when they had not yet sorted out their software tuning. Generally, one would expect 0% drain for days at a time, as has been observed with a car left in a parking garage for a week and charged to 80%. To investigate this issue further, it is important to consider the charge level before the 5% declines, whether the car is sitting in direct sun, if it is making any noise, and if rebooting the car helps.

For instance, one user left their car at the airport for almost 3 weeks at 92%, and returned to 92%, with no decrease in battery % while parked overnight. Another user went away for a week with their car left in front of their parents’ house (in summertime temps) and did not lose a percent. It may be helpful to set up daily preconditioning before leaving the car, as this can cause cooling/heating every day at the preset time (also on battery), which can consume 4-5 kWh.

It is also important to check if unlock on approach setup is enabled for keys/digital key, and if the location of the car is within range of where you have the key/phone. Additionally, make sure that your car is turning off after exiting by setting up the option to turn off when exiting. After walking away from the car, go back out to the car an hour or two afterwards to see if your screens are still active and alive.

In conclusion, it is important to investigate further when observing unexpected battery drain while idling. Consider factors such as charge level before decline, location of the car, noise made by the car, and settings related to unlocking and turning off after exiting. With these considerations in mind, it should be possible to identify what is causing the unexpected drop in charge while idling.

What charge level are you starting at before these 5% declines?

It is recommended to start at 80% charge level before the 5% declines.

Is the car sitting somewhere in direct sun that its baking all day?

If the car is exposed to direct sunlight, it may cause the battery to drop.

Does the car sound like its on / making any sort of noise?

If the car is making any sort of noise, it could be an indication of a problem with the battery.

Have you tried reboot the car to see if this persists after?

Rebooting the car can help determine if the issue persists after.

Do you have unlock on approach setup for the keys / digital key?

Unlock on approach setup for keys and digital key can help prevent unnecessary drain on the battery.

Are you sure your car is turning off after exiting the car?

There is a setting to turn off the car when exiting, which should be enabled to ensure that screens and systems are not left on all night long.

Are you sure the car is not in sleep mode?

If the car is in sleep mode, it will draw a small amount of power from the battery. To prevent this, make sure to turn off the car when exiting.

Is there any other device connected to the car that could be draining the battery?

It is possible that other devices connected to the car are draining the battery. Make sure to disconnect any unnecessary devices or accessories when not in use.

Have you tried resetting the battery management system?

Resetting the battery management system can help restore balance and efficiency to the battery. This should be done if all other solutions have been exhausted.

Is there anything else I can do to help?

If all else fails, it may be necessary to replace the battery or take it to a professional for further diagnosis and repair.