“I Found the Battery (Eventually): A Foolproof Guide to Accessing, Monitoring, and Laughing at Yourself Inside a BYD Atto 3”
By Someone Who Has Now Earned a Wrench Emoji in Their Bio
Chapter 1: “Where the Hell Is It?”
You may think your Atto 3’s 12V battery lives under the bonnet, like a normal car. You’d be wrong. Very wrong.
After a solid ten minutes of poking around up front and using increasingly colourful language that probably taught the AI helping me a few new expressions, I discovered the truth:
It’s under the driver’s seat.
To find it:
- Slide the driver’s seat as far forward and upward as possible.
-
Gently lift the carpet flap behind the seat base – think “surgical precision,” not “ripping open a bag of Twisties.”
-
There it is: the elusive STEK-3703030A / DJ1BB0 12V LiFePOâ‚„ battery, glinting smugly beneath its black plastic fortress.
Chapter 2: Accessing the Beast
You’ll need:
A flathead screwdriver to unclip the cover (there’s a small tab – marked with a yellow line in the image – that you gently pry open).
A 10mm socket wrench to loosen the terminal nuts.
A calm temperament, or failing that, coffee.
Once inside, you’ll spot two terminals:
The positive terminal (+) is under a black cap with a visible plus sign.
The negative terminal (-) is a metal clamp with a minus symbol stamped next to it. You’ll know it because it doesn’t have a cap and looks boring.
Both are marked in one of the photos with yellow lines “” the end result of some spirited debate between me and reality.
Chapter 3: Bluetooth Wizardry
With the terminals exposed, I installed a Bluetooth battery monitor:
Red wire to +
Black wire to –
The app read: ✅ 13.05V / 98% SoC. That’s what success looks like, baby.
See the screenshot image: voltage, temperature, state of charge, and the sweet, sweet confirmation: Battery OK.
This lets you monitor the health of your 12V battery in real-time, which is essential if your EV sits idle for long periods.
Chapter 4: Preparing for the Trickle-Down Revolution
With terminal access sorted, I’m off to buy a LiFePOâ‚„-compatible trickle charger. Why?
Because:
Lithium batteries hate going flat
Jump-starting an EV is risky business
And I’m not pulling that carpet up again if I can help it
There’s even a clever photo showing the flap that can be lifted to insert the charger lead without full disassembly – marked clearly for your sanity.
Chapter 5: Lessons from the Pit of Carpet
It’s always the last place you look, especially when that place is under your butt.
Sometimes, the guide is right – especially after the third try.
And yes, your EV has a 12V battery. It’s just playing hard to get.
Final Tips for Future Battery Adventurers
Always remove the negative terminal first when disconnecting
Use LiFePOâ‚„-specific chargers only
Bluetooth monitors are lifesavers
And never underestimate the power of seat height adjustment.
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😀 I see BYD now have their own branded ships taking their vehicles to the world.
My 1964 VW beetle had the battery under the back seat.
Gosh !
In my Hyundai Ioniq Plugin, the 12v battery is in one of those side pockets in the boot. It also has a vent pipe that goes into the wheel arch so anything noxious can escape.
It’s under the driver’s seat in a Porsche Cayenne too
I hate feeding into gender stereotypes, but did it ever occur to you to read the manual?
I have no manual unfortunately. They ran out. I’ll get one next service. The electronic manual on the infotainment system didn’t tell me either.
So short answer, yes, it did occur to me! 😉
I’ve also learned to disregard the SoC and go by the voltage on my monitor. AI has helped me to understand how healthy the battery is by sharing my battery monitor readings over time. Good news, it’s very healthy. Even better I’m beginning to understand how to keep it that way (getting the high voltage battery to charge the 12 volt). I also know that if I go away for 3 weeks or more to not only leave the wall charger connected but also to connect my 12 volt trickle charger.
As someone commented, it’ll be a learning curve and you will learn.
I have and still am! 😊