Which parts fail
Components named in complaints (battery, alternator, wiring, ignition, instrument cluster, infotainment).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2021 Kia K5 owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2021 Kia K5. The contact stated that while driving at various speeds, the Lane Assist feature would illuminate without other vehicles nearby. The contact also stated that the vehicle would independently switch lanes independently; causing the contact to forcefully adjust the steering wheel into the desired lane to prevent a potential crash. The contact manually disabled the features; however, the features independently reactivated. In addition, the defroster failed to operate as needed which obstructed her vision due to fog on the windshield. The vehicle was initially taken to a dealer, but the contact was offered no assistance. The contact then took the vehicle to Kia of Irvine (45 Oldfield Building B, Irvine, CA 92618) where two mechanics acknowledged the failure while test driving the vehicle. …
Kia has a known issue with the HVAC blower motor circuit on this vehicle model. They have issued a warranty extension related to relocating the blower motor fuse to another circuit in the fuse box, due to potential burning of fuse(s). After executing this extended warranty fuse-relocation-procedure, our blower motor relay burned and was replaced twice by separate Kia dealers. Kia is now claiming that our entire wire harness needs to be replaced at our own cost. It is quite obvious that any wire harness issue is now very dangerous (electrical arcing and melting) and was caused by the original motor circuit issue. …
The contact owns a 2021 Kia K5. The contact stated that the driver assist feature would activate independently. The contact stated no warning light was illuminated. The contact was able to park on the side of the road and shifted from park to drive to deactivate the driver assist feature and continued driving to his destination. The contact called the local dealer and made them aware of failure. The vehicle was not diagnosed or repaired. The manufacturer had been informed of the failure. The failure mileage was 32,077.
I am submitting this complaint regarding a leaking evaporator core in my 2021 Kia K5. The evaporator core failed at approximately 59,600 miles, causing the air conditioning system to stop cooling properly. The vehicle was diagnosed by a repair facility, which determined that the evaporator core was leaking refrigerant and required replacement. An evaporator core is a major HVAC component that should not fail at such low mileage under normal operating conditions. This failure affects the vehicle's ability to properly dehumidify and defrost the windshield, which can reduce visibility and create a potential safety hazard during rain, high humidity, or cold weather conditions. I have maintained the vehicle as recommended and believe this component failed prematurely. Due to the extensive labor required to replace the evaporator core, the repair cost is significant. …
Within three days of purchase, the vehicle experienced a fuel system failure requiring the gas tank to be replaced. Shortly afterward, the check-engine light illuminated, indicating additional engine or emissions problems. The failures occurred without warning and made the vehicle unsafe to drive. The engine warning has continued to appear, suggesting a recurring or unresolved malfunction. The defects create risks including fuel leakage, stalling, engine shutdown, and potential fire hazard. The safety of the driver and others on the road is put at risk because the vehicle may fail while in motion. The problem appeared immediately after purchase and continues to recur. The dealer was notified but refused to diagnose or repair the vehicle further. No manufacturer inspection has occurred because the dealership declined to provide service. …
The vehicle experiences severe stalling and loss of power while driving. When attempting to accelerate, the vehicle hesitates, shakes violently, and will not accelerate beyond approximately 10-20 mph. The vehicle then stalls completely and shuts off. These failures occur both after the vehicle has been parked and while actively driving. When placed in drive, the vehicle shakes aggressively and stalls. The check engine light is illuminated. The stalling has occurred multiple times in the middle of freeway traffic, creating an extreme safety hazard. My child has been in the vehicle during every occurrence. On one occasion, the vehicle shut off completely while on the freeway, placing our lives at risk and nearly resulting in a serious collision. This issue is unpredictable, persistent, and prevents safe operation of the vehicle. …
My 2021 Kia K5 EX has a severe and unsafe steering problem. The vehicle consistently pulls hard to the right on its own, even on straight roads. If I loosen my grip even slightly, the car immediately veers to the right. The steering wheel does not stay centered, and I have to constantly fight the steering just to keep the car in the lane. This issue has continued despite multiple alignments, tire replacements, and inspections. Nothing has fixed the problem, and the steering behavior feels mechanical or electronic in nature. I no longer feel safe driving the vehicle because it feels like I could lose control at any time. Additionally, my vehicle is affected by the open recall (SC356 / NHTSA 25V794) involving fuel tank expansion and fire risk. The status says 'Incompleted - remedy not available,' meaning there is currently no repair solution. …
Engine code came on, one interior headlamp works when it wants to, climate control module is bad it has cause the relay to blow and the resistor to go out. The air turns up on the control module by itself and then your ac just stops working and then starts again as it chooses. All of these are electrical issue as stated in MANY OTHER reports. And electrical issue is unsafe it can cause fire at anytime, my car is new 2021 Kia k5 Lxs, 60k miles and now who knows when the car is going to catch fire while my baby is strapped in a car seat and no AC . RECALL before lives are took from heat stroke or possible fire. To be "luxury" it's sad I just paid my 3rd car payment and now I can't even drive my car. Over 100 reports on this same problem and y'all do nothing. Kia is maybe at 70k sells a year now meanwhile Toyota and other are at 300k. …
For breaks: at 20k miles the steering wheel shakes like crazy when braking, and also the pedals: the rotors are very cheap for being a 0-mile purchase vehicle and Kia does not replace this under warranty. I saw a forum that this is an issue for all owners of this Kia K5 and Kia doesn't care and does not replace them. For Electrical issue: the fuse box melted a couple fuse because I used my rear defrost system. Kia extended the warranty for the HVAC motor fan only because was burning the fuses, but they did not wanted to replace my issue with the rear defrost because I was above 60k for only 1000 miles. This is a poor-quality system, Kia does not recognize it. This is a safety issue because 1. There is an electrical issue with a melted fuse box. Im driving around a car like this with 2 kids. 2. I don't have rear defrost working and I live in Chicago (wild winter). …
At the beginning at the year I had to change my starter because my car would leave me stranded on the street, at a stop light or any time my car would stop. I was once in the car with my little brother and in the middle of the street it would not start again and left us stranded. Others around me had to help me push the car to the side of the road that way I wouldn't be rear ended. Now, I'm having other issues such as HVAC were my cars AC does not turn on. It doesn't even blow hot air. Some mechanics have told me it's probably my blower and resistor and other that it's a wiring issue. My car is only 4 years old and should not be having so many issues. I have tried reaching out to Kia but always get sent to voicemail or have told I would be charged for it to just be seen. If anyone could help me with my car that would be greatly appreciated.
Electrical complaints in other K5 years
Frequently asked questions
How common are electrical problems on the 2021 Kia K5?
NHTSA has 46 complaints about the electrical system of the 2021 Kia K5, 27% of the model year's 169 complaints. The component named most often is horn (1 mentions).
Is there a recall for 2021 Kia K5 electrical problems?
No. NHTSA lists no electrical system recall for the 2021 Kia K5, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2021 Kia K5 electrical problems start?
Half of the complaints with a recorded mileage happened before about 18,000 miles, and 75% before 25,000 miles.
Is it dangerous?
Owners linked 0 crashes, 2 fires and 0 injuries to electrical system problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.