These instructions apply to the Hyundai Kona Mk1 (OS) 2017-2023.
For other models, please choose your vehicle here.
A flat 12 V battery leaves the Kona completely dead — no dash, no start. On the Kona Electric this small 12 V battery is separate from the high-voltage drive battery, and you bring the car back to life by jumping it at the terminals under the bonnet, then letting it recharge.
Jump-start the Kona 12V battery
- Bring a donor car or a jump pack close enough for the leads to reach — but the two cars must not touch.
- Switch everything off in both cars: lights, climate and the POWER (or ignition) button OFF.
- Open the Kona’s bonnet. The 12 V battery and its red positive (+) jump terminal are in the motor compartment on the right.
- Connect the red lead first: one clamp to the Kona’s red positive (+) jump terminal, the other to the donor’s positive (+).
- Connect the black lead: one clamp to the donor’s negative (−), the other to a bare metal chassis earth point on the Kona — not the battery’s negative post.
- Wake the Kona. On the Electric, press the POWER button to reach READY (it does not crank); on a petrol or hybrid Kona, start the engine as normal.
- Leave the car in READY (or running) for at least 30 minutes — it recharges its own 12 V battery.
- Remove the leads in the exact reverse order (Kona earth, donor negative, donor positive, Kona positive) and close the bonnet.
Never jump a frozen battery, never touch the orange high-voltage components while the car is powered on, and do not try to push- or tow-start it — that will not work and can cause damage.
Frequently asked questions
Where is the 12 V battery on the Kona Electric?
In the motor compartment (under the bonnet) on the right — a small conventional 12 V battery, completely separate from the high-voltage drive battery under the floor.
Why does my Kona’s 12 V battery keep going flat?
Leaving a door or the tailgate ajar, or using accessories while the car is not in READY or Utility mode, drains the small 12 V battery. A longer drive, or leaving the car in READY, recharges it. A 12 V that dies again and again should be load-tested and probably replaced.
Can I jump-start another car from my Kona?
No. The 12 V battery is small and there is no alternator to sustain a heavy draw, so you risk flattening your own car. Use a separate jump pack for the other vehicle.
If a warning light or fault code stays on after the battery goes flat, you can look it up on autodtcs.com.
Independent guide — not affiliated with Hyundai. Always follow your official service manual and safety precautions. Read our full disclaimer.