Hyundai Kona Safety Issue

Hyundai Kona – Safety Issue Notification

We have identified a serious safety issue with the latest version of the Hyundai Kona (2020 model with three phase onboard charger)

In certain circumstances, when used with an EV charger such as the myenergi zappi which supports both three phase and single phase charging, the Kona causes a short circuit across the supply.  This can cause:

  • The main fuses to the property to blow – these will need to be replaced by the electricity distribution or supply company at a cost to the customer
  • Damage to the zappi – the zappi will need to be repaired or replaced
  • Possible damage to the EV

Although we have been made aware of the Hyundai Kona Safety Issue by our customers we are also aware that other EV charge points have encountered similar problems with the new Kona as well as the Kia e-Niro and the Kia e-Soul


Hyundai have now confirmed that new firmware is available for their EV’s with three phase on board chargers.

We understand that they will be contacting the owners of all EV’s concerned to arrange a firmware update  from the service centre



Why does the Hyundai Kona cause this problem?

If the Kona is charging from a single phase supply it appears to use a relay to physically connect the supply phases L1 and L2 together – presumably because the car has two 3.6kW single phase chargers that need to be connected in parallel to charge at 7kW from one phase.

When the zappi switches to three phases it follows this sequence

  • Instructs the car to stop the charge
  • Opens the output contactors, completely isolating the output to the EV
  • Sends a reset sequence to the car (using the Control Pilot wire)
  • Restarts the charge in three phase mode
  • When the EV confirms that it is ready to charge the output contactors are closed again.

All other EV’s that support three phase charging (such as the Tesla Model 3 and Renault Zoe) respond as expected and charge safely.

Unfortunately, the Hyundai Kona safety issue means it does not respond to the above sequence and leaves the relay shorting L1 and L2 energised even though the supply has been isolated, causing a short circuit when the zappi starts the three-phase charge.

What are we doing about the Hyundai Kona Safety Issue?

Although the problem is caused by the Hyundai Kona, we want to make sure that our customers are safe.

As well as doing what we can to publicise the issue, we are also working on new firmware for the zappi that will detect if there is a potential safety issue and prevent the change from single phase charging to three phase charging.   The aim is to make this firmware available by Friday 24th July 2020.

Unfortunately, this change may also limit other cars that can work safely.   We are not happy about this and will continue to do whatever we can to influence Hyundai as well as working on the firmware to find ways to only detect potentially dangerous vehicles and allow all others to charge flexibly as designed.