Will the 12V battery drain while using accessories?

[Chosen_Undead]

I’m taking my Audi Q4 E-tron camping next week, and I was planning to use the 12V socket to run some lights and charge devices overnight. With a nearly full 77kWh battery, I figured there’d be plenty of capacity, but now I’m wondering…

- Will the 12V battery drain completely if I leave devices plugged in?
- Does the main high-voltage battery keep the 12V battery topped up automatically?
- Has anyone run accessories off the 12V socket for an extended period without issues?

I’d rather not wake up to a dead 12V battery in the middle of the woods

 

[Horizon.tron]

I’ve been thinking about that too. I could be wrong, but my guess is that when the drivetrain is on, the main battery charges the 12V battery. Howevr, when the drivetrain is off, it’s likely the 12V battery drains. Hopefuly, someone with more knowledge can confirm!

 

[EtronDriveR2024]

I’ve been thinking about that too. I could be wrong, but my guess is that when the drivetrain is on, the main battery charges the 12V battery. Howevr, when the drivetrain is off, it’s likely the 12V battery drains. Hopefuly, someone with more knowledge can confirm!

Yes, you are right! The hv battery doesn't charge the 12v battery when it is parked. It is useful to have a portable Li jump starter for situations like this one.

 

[Edgeofnight63]

Will the 12V battery drain completely if I leave devices plugged in?

Nope. The hv battery maintain the 12v system only until the main battery drops below 15%.