Charging challenges with Kia e-Niro, Kia e-Soul & Hyundai Kona 2020

Update 26.11.20

A number of tests have now been carried out and new software has now been completed which corrects this error. We recommend that anyone who has a car supplied with a 3-phase on-board charger (11 kW) before October/November 2020 contact their dealer to get this update. It is a Service Action that is active from KIA Norway and will basically be updated at the next service.

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A security issue was identified with the latest version of the Kia e-Niro (2020 model), Kia e-Soul (2020 model) and Hyundai Kona (2020 model) with built-in 3-phase on-board charger.

Under certain circumstances, the vehicles will short-circuit the power supply when used in conjunction with a charging station that supports both 3-phase and 1-phase charging. This is especially the case when switching from 3-phase to 1-phase charging (load and phase balancing). This can lead to:

• The main fuse trips and must be flipped up. Alternatively, it must be replaced if it has been damaged
• Damage to the charging station / charging equipment - the equipment is repaired or replaced
• Potential damage to vehicle / car

We have been made aware of this problem by our customers, and we know that the problem affects several charging boxes. We have already informed our manufacturers about this challenge.

To protect all our customers, we recommend either:

• Disable phase balancing
• Only to charge with either 1-phase or 3-phase
• If you are going to switch between 1- and 3-phase charging, you must disconnect the car first

What is the cause of this problem?

Normally when the vehicles charge with more than 16A from a 1-phase supply, the majority of cars use a relay to physically connect the supply phases L1 + L2. As many vehicles have two 3.6 kW 1-phase chargers, these are connected in parallel to be able to produce 7.2 kW from a charging box with 1-phase supply.

The usual sequence for charging and phase balancing / changing phases:

• The charging station instructs the vehicle to stop charging
• The charging station opens the contactors and isolates the output to the vehicle
• The charging station sends a reset command to the vehicle via the CP cable
• Then restarts the charging process in 3-phase mode
• When the vehicle signals that it is ready to charge, the contactors close to allow current to flow through

In this case, the vehicles have 3 1-phase chargers of 3.6 kW which produce a total of 11 kW with 3-phase charging. The challenge seems to be when the charging stations want to go from 1-phase to 3-phase charging, the vehicles do not disconnect the relay between L1 and L2 (despite the reset signal) and thus short-circuit L1 and L2 despite the power supply being isolated before the contactors switch on again.

All other cars that support 3-phase charging such as e.g. Tesla Model S/X/3, Renault ZOE, Audi e-Tron etc. react as they should and charge safely.