2024 Kia EV9

Starting on Feb 22, 2025, we observed that our Kia EV9 had dramatically reduced range. Normally, when charging was complete the dashboard would show well over 250 miles of range, even in cold weather. On Feb 22nd we started to see the range had dropped to around 60 miles, even when the dashboard reported the battery at 100% charge. The actual range seemed to be even worse, dropping dramatically even after a short drive around our town. By all appearances, the high voltage battery seems to be defective and is causing a safety issue because it could result in a sudden loss of power during driving or an unexpected shutdown of the vehicle. This may also be a symptom of an even more serious battery defect that could result in a battery fire. We brought the vehicle to the dealer, and they were able to reproduce the severe drop in range. No components have been replaced yet, we are still waiting to hear which parts will be replaced under warranty service. During this entire time the vehicle has given zero warnings or alerts, including no warning messages nor the check engine light.

We heard a grinding sound from rear of vehicle while driving into a park lot. Checked road and vehicle to see if there was any damage or objects hit, there were not. Shortly after driving a few miles a BMS warning was showing and we called Kia roadside assistance. They insisted on towing the car but we waited until next day so we could secure a rental. The short drive to the rental agency now gave us 4 more errors regarding “check 4WD/AWD” and the code was given as “MCU_R” to check the rear motor control units. All were listed as “P1Axxxx” errors. During this time, electronics in the car did not work well, vehicle did not want to shift into gears and acceleration was noticeably degraded. Car is at dealership being worked on now.

Vehicle range went from 320+ miles on a 100% charge to just 100 miles on 100% charge. Looks to be a bad battery cell or battery itself. No warning lights of any kind. Just super degraded range. Vehicle is new and has around 5800 miles. Dealer doesn't have techs to work on batteries, so they are having to play telephone game with Kia tech line in Korea.

3 weeks after picking up our Kia EV9, I noticed a thunking sound from the passenger side front tire. When we reached home, we opened the car cover and noticed that the lug nut had come off and was rattling behind the cover. We called the dealership and the asked us to bring the car in. Since we didn't want to drive it, we bought a torque wrench and tightened it ourselves, after getting the information from the dealership on how much to tighten it. We also noticed that all the lug nuts were under torqued and the driver side lug nut was very loose. I also read multiple reports on online forums (Reddit) about new Kia EV9 wheels flying off on the highway.

Certain ADAS features have disengaged at least six times in the last year. While traveling at greater than 55 mph vehicle disengages cruise control and reports numerous warning indicators on dashboard including ADAS forward features such as collision warning and automatic braking indicators. I also noted lane management/steering also seemed to disengage when this has occurred during highway curve management. It is difficult to evaluate the full range of loss as the dashboard warnings are numerous and change over the next few minutes. It is also unsafe to secure good photographic evidence when traveling alone, though with assistance some imagery was recently captured. The sudden loss of speed and directional control assistance in multi-lane urban traffic was alarming but managed OK by alert driving. The manufacturer's dealer reported they could do nothing after one of the first occurrences. They said there were not 'codes' registered and not reports on file. The loss of systems usually cleared up within a few miles for the first instances. The most recent case persisted for several hours and several vehicle off/restart cycles. During this time the dashboard indicators suggested some failures resolved but some remained. This last case cleared over-night upon morning restart. A failure/warning was noted in the Kia Connect online app while the car still reported a problem. There were no prior indications before the sudden systems failure. All of these cases initially occurred on a section of road within about 1/2 mile of the same place. It involves a significant curve on an urban interstate interchanged. Sometimes the failures occur just before, or during, and at the end of the curve.

The back end of the car will move back and forth laterally when driving over uneven road. In particular it appears to happen when driving over a bump while also driving at a slight left or right angle. After the bump the back end will oscillate laterally. This is extremely concerning to the driver and passengers, it can feel like the car is going to bounce out of its lane.

I am experiencing significant and persistent vibrations at highway speeds (60–75 mph) in my 2024 Kia EV9. Despite multiple dealership visits and repair attempts, the issue remains unresolved. The vibrations cause noticeable discomfort and potential safety risks, especially on long drives. Timeline of Events & Repairs: 1.First Visit to Kia dealer (Dec 24): The dealership performed a tire balance and determined one tire was defective, replacing it. Vibrations persisted. 2.Second Visit (Jan 25) The dealership replaced the remaining 3 tires 3. ThirdVisit (Feb 25): The dealership identified three wheels with lateral runout and replaced them. They also performed road force balancing, reportedly bringing all values below 16. 4.Test Drive (Feb 25): After picking up my vehicle, I drove on the interstate and found the vibrations had worsened, now starting at 60 mph instead of 70 mph. •A third-party wheel shop inspected the wheels and found the fourth wheel (not replaced by Kia) was defective and out of round. 5.Dealership’s Response: Despite these findings, Kia dealer dismissed my concerns and referred me to another dealership for a second opinion. They also stated that third-party evaluations are not accepted, creating an endless loop where I cannot get the issue properly addressed. Safety Concerns: •Vibrations impact vehicle stability and driver comfort, especially on long trips. •Extended driving with excessive vibrations may lead to fatigue, reduced control, and premature mechanical wear. •The fact that multiple components (wheels, tires) have required replacement raises concerns about a potential manufacturing defect affecting Kia EV9 models. Request for Investigation: The dealership has failed to resolve this issue despite multiple repair attempts, and their refusal to acknowledge third-party findings leaves me with no clear resolution path. I request that NHTSA investigate potential defects in the wheels, tires, or drivetrain system of the Kia EV9.