Hyundai Kona Won’t Start – Top Tips to get you going!


Owning an EV is fantastic and good for your pocket and your emissions, but no car is good if it won’t start! I’ve been a mechanic for 25 years. Let’s solve why your Kona EV won’t start and get you back driving.

The most common reasons your Kona EV won’t start include:

  • No charge in your High Voltage battery
  • Problem with the charging
  • Dead 12V battery
  • Dead key fob

In this article, we’ll look at why your Kona won’t start and how to go about fixing the problem.

Kona-won't-start

No Charge in Your High Voltage Battery

The top reason that your Kona EV won’t start is the high-voltage traction battery is flat. The traction battery is what powers the car to drive. The question you have to ask is, why is it flat? The number one reason is that charging didn’t happen, even though you plugged it in the previous evening. There are two reasons why charging doesn’t occur if it is plugged in:

  • Power outage
  • Charging problem with the car

Power Outage

There are many reasons why we have power outages: climate, scheduled shutdown, or circuit overload.

Owning an EV has many perks, but one of the downsides, unlike owning an ICE car, is that we have to particular attention to the weather. If we know a storm is coming, we can prepare. We can either pre-charge our car at home or a fast charger or have a power generator as a backup for such occasions.

Our weather has become increasingly unpredictable, but thankfully most fast chargers have solar power or an alternative backup.

Many States, predominantly California, have scheduled outages or power shutdowns because of too much draw on the grid at certain times of the day or week. Again you can plan for this.

The one you can’t plan for is a circuit breaker. This occurs during charging, the circuit to which your cable is connected shorts and trips the power. You may not be aware it has happened until you check your car, as many homes are zoned, only that zone has gone down (Garage), and you had no reason to be in that area since you plugged in your car.

Usually, circuits trip because of overloading or something shorting out. Overloading is not unusual when heavy electric items are plugged into one zone simultaneously. A short is commonly caused by something as simple as a nick in your cable that comes into contact with moisture.

These are all positive reactions, even though it doesn’t seem that way, as your car has not changed, but without these reactions, we would be dealing with a fire. This leads me to the next possibility of no charge.

Car Charging Issue

There are other charging issue possibilities, such as: Was the cable plugged in properly? Did someone unplug your car accidentally? But the one we are going to look at is the Hyundai charging issue that comes from the faulty battery in the 2019 – 2020 Kona models (and also Ioniq).

Hyundai Kona (and Ioniq) models have had some very bad press regarding their high-voltage batteries. We can’t talk about charging problems without discussing the recall. The 2019 – 2020 models were fitted with high-voltage Li-Ion batteries manufactured by LG Energy Solutions in China. The fault arose when the Anode came into contact with the Cathode, resulting in a short, that in turn, could lead to a vehicle going on fire.

Cars and fire are not good! Kona owners were initially asked to park outside and limit their charging to 80% max, to reduce the heat going to the battery while charging.

Hyundai carried out a software update that prevented full charge from happening. Although only a handful of Konas has actually gone on fire (and none in the US), it is believed that the software update did not solve the problem. A full battery replacement is required, leading to the biggest (most expensive) EV recall to date.

The battery issue could be the reason you can’t start your car. The notification on the dash ‘Check Electric Vehicle System Error’ appears if the safety checks during charging don’t go to plan, i.e., if the BMS (Battery Management System) detects anything unusual, it will prevent charging from going ahead. It is an absolute pain, but it comes from an overcautious Hyundai, ensuring no more cars go on fire.

If you thought your car was charging all night and then realize it wasn’t, because of this reason, you now have a dash message that not only won’t allow you to start your Kona but possibly needs the car to go to the dealership for the error to be cleared, or possibly worse again, a new traction battery replacement.

In 2022, Hyundai released an updated Kona EV with a new battery from SK Innovation. Hopefully, these major problems are behind them.

Everyone who drives an EV wants the security to know that they can go to their car in the morning and it will start and get them to their destination. Range anxiety comes with owning an EV. Your car going on fire is a definite no-no.

Dead 12V Battery

Your Hyundai Kona has two batteries. The high voltage traction battery and also a traditional 12V battery. The 12V runs all auxiliary items such as locking, windows, and media. If your 12V is flat, then the car won’t start. Along with the high voltage, the 12V must be charged for everything to work correctly.

So how do we get the battery going again? A 12V needs over 12V to work. If it’s flat, we need to gain access to it. It lives under the hood, and because it’s flat, unlocking your car won’t be possible with passive entry or the smart fob.

First things first, we need to unlock the car to gain access to the hood lever.

Thankfully the fob has a mechanical key inside. To remove the key from the fob:

  • Slide the button on one end
  • Remove the key

The keyhole is on the driver’s door handle. Don’t forget to reassemble your fob when you’re done. The key is not fully seated until it clicks.

Now that the car is unlocked locate the hood lever. It lives on the driver’s side to the left, in the footwell. It has a small icon of an open hood on it.

Pull it towards you. It might require some force if it hasn’t been used very often.

The hood will pop, but a latch under the center part of the hood requires you to slide it to the left. Prop the hood with the bar and insert it into the small hole at the top left.

Boost the Battery

We’re finally in and can locate and check the 12V. It’s located on the right, just behind the headlights. Bright orange cables represent the high voltage. Don’t Touch Them!

Remove the terminal caps for both the positive and negative. You can check the voltage with a battery charger. Anything less than 12V+, your battery requires a boost.

A booster is the better option but not always practical or available. You can jump your car from a donor gas car but never another EV.

Either way, the cables need to be attached in a particular sequence.

  • Connect the Red (+) to Red (+)
  • Connect the Black (-) to Black (-)
  • Your battery charger will give you a reading of the voltage in your battery if it’s a digital booster.
  • Turn on the battery pack
  • When 12V+ is achieved disconnect the cables in the reverse order
  • Black and Black (-)
  • Red and Red (+)

The 12V doesn’t actually power your car to drive, so if there’s a charge in your high voltage, as soon as the 12V is back, you should be able to start your car.

Dead Key Fob

Another reason your Kona won’t start is because your Key Fob / Smart Key battery is flat. The key fob allows you to lock / unlock your car and also starts the car (it needs to be in the car with you).

To replace the fob battery, you first need to remove the mechanical key (as before). Turn the fob upside down – buttons facing down. Where the key has been removed, you can see a slight groove below the hole. Slide a blunt knife or file into the groove and twist gently. This should break the fob in two.

Gently slide the old battery out and replace it with a new battery. The battery is a CR2032 – widely available online and in-store. Try not to touch the contact side. Slide the new one into place plus (+) side up. Snap the case back together and reinsert the mechanical key.

Although the battery in your fob is very important, it shouldn’t completely prevent your car from starting. All fobs have internal chips that the car’s computer recognizes. If you hold a dead fob near the start/ stop button, it may activate your car. But best not to take any chances. Always a good idea to have your fob in tip-top condition.

Other posts you might find useful:

Can I jump start my Kona?

Hyundai Kona Charging Door Won’t Open

Hyundai Kona Won’t Lock

E John Cunningham

Hey, I’m John and I'm a technical writer here at EVjuicedup.com. I’m a Red Seal qualified Auto Service Technician with over twenty-five years experience working on Classic and Modern Cars. I've worked for GM, Jaguar, Land Rover, Volvo, Audi, and VW main dealers. Yep, I’ve skint my knuckles on them all!

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