2018 KIA OPTIMA Electrical System Problems

I turned the car off, it had difficulty turning back on and the brake pedal got really hard. I had to wait about 30-45 minutes and then I was able to get the car started and brake pedal back to normal and no lights. Recently, I left the car on to run into a shop real quick and come back out. When I got back to the car, the power steering light, battery, and warning light?(amber triangle with ! In the center of it) were all on. I rev the engine and the issue went away for a quick second but then came back on. To avoid turning my car off and being stuck, I just shift to reverse and tried to leave. I’m backing out of the spot and now the backup camera is going in and out lights flashing on the dash and I’m trying to brake but the brake pedal isn’t registering and next thing you know, I’ve backed into a guard rail. On the way to drop my kids off at the babysitter, I was coming to a stop sign, and my car wouldn’t brake, i went through oncoming trafic and had to run off the road. KIA did a multi point inspection a few months apart from one another. One the car tested fine, then the second time they are saying a brake booster and no engine oil in the vehicle and that the car is basically trash. The oil light goes on and off and I can smell burning oil. I still owe 7 grand on this car and I just bought it last year and it was seamingly fine.

I was sold an unsafe vehicle at J and J Auto house 6446 Wilshire Bl LA,CA 90022. Dealer withheld condition of car . Had car three months and was stranded on highway. Car was towed to Kia dealer and diagnosed with complete engine failure. Dealer will not honor limited warranty, shady sales practices withheld recall info during sale, won’t allow his mechanic to look at car, dodged calls, denied request to return car for refund

On August 26, 2025, I brought my 2018 Kia Optima Plug-In Hybrid to an authorized dealer for recall SC218 (engine inspection and KSDS software update). The dealer verbally stated both SC218 and SC278 recalls were completed, and the repair order (RO #XXX) lists them as performed. In September 2025, Kia America emailed me showing recall SC218 still open, and a warranty coverage report dated September 26, 2025, again listed SC218 as unclosed. On November 4, 2025, NHTSA’s official VIN lookup confirmed the recall remains “Incomplete.” On October 21, 2025, Kia America emailed me under Case #XXX stating that SC218 was “confirmed completed” and that the dealer performed a software update to the ECU, referencing RO #XXX. However, NHTSA’s database still lists recall SC218 as incomplete. This contradiction between Kia America’s internal record, the dealer’s invoice, and the federal NHTSA database raises a serious safety concern that the recall inspection or software update was never actually performed or was never reported correctly. I have requested written proof and diagnostic data (Battery SOH report) multiple times but have not received them. If accurate, this means I was led to believe my vehicle’s engine-safety recall had been repaired when federal records still list it as open. I am requesting NHTSA to review this reporting discrepancy, ensure Kia America and the dealer produce verifiable proof of completion, and confirm that the federal record is corrected. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My cars bulbs have been blowing on a regular basis for two years..some of the bulb connections are catching fire and exploding .Ive changed on numerous occasions but doesn’t matter even with new fittings…obviously an electric problem

The car is literally burning through oil so bad every other week I am putting more in, the electrical system continues to fail and shorts, the motor sounds like it is ticking now due to the oil consumption.

There is already the theta 2 campaign on my Kia optima but Kia is not upholding their warranty for a new engine. Kia customer care told me that untill my car actually throws a rod then they will not fix it. So I could be doing 80 down the freeway and jeopardize not only my safety but everyone else's for them to uphold their lifetime warranty? Also upon doing further investigation and I don't know how many cars this pertains to but the fuse box in my 2018 actually belongs to a 2016 which if you look it up yes they are comparable but don't offer all the same functions or power that my 2018 needs to run I fully believe Kia knew this when they were being built on the factory line because it just so happens that there is about 6 different versions to the pcb relay that can fit from a 2016 to a 2020 k5 but for some odd reason every car got something different why?

While driving at night if the headlights will randomly turn completely off

Engine is burning oil at a high rate have to add at least three quarts twice a week and headlights and brake lights got out twice a month

Oil pressure switch faulty only has 58168

In case of a vehicle lockout and keys are locked in the trunk when car is opened by locksmith there is no way to unlock the trunk from inside of the car the locks become disabled and you have to reset the master switch very inconvenient for emergencies. There is no trunk release or emergency Button to open the trunk from inside the vehicle. 2018 kia optima lx

Was driving on the interstate. The only light on was the ABS light and the car started smoking. Had to come to a stop as they were sparks coming from out under the car through it into park at around 15 mph steel jumped out of the car and within a minute the car was fully engulfed in flames.

The contact owns a 2018 Kia Optima. The contact stated that the vehicle was sputtering while being started. The contact stated that the vehicle also sputtered while driving at various speeds, and while reversing. The check engine warning light was illuminated. The vehicle was taken to the dealer and the contact was informed that oil was getting onto the spark plugs and ignition coils. The spark plugs and ignition coils were replaced; however, the failure persisted. The manufacturer was not made aware of the failure. The approximate failure mileage was 70,000.

Mileage: 70,000

The engine consumes all the oil within 1000 miles. The oil light comes on around 800 miles after oil change. The dealership did the 3 separate tests and they all failed. Dealership stated the engine is faulty however Kia corporate denied the claim. There is already a class action lawsuit in progress in California.

Normally, when the doors are open my car will tell me. The doors notify me that they're open but my trunk was not showing that it was open. It blinks when it is. Due to that I was driving and my trunk seemed closed and it just flew open. So the problems I'm having is that my trunk will not show its open but it also will not close AT ALL due to the latch. I literally had to bungee it closed. This is dangerous. I have seen many recalls in other kia's and hyundai's just like this. This is very dangerous and needs to be recalled and/or fixed.

Rough idle, chugged along before killing engine power. Has happened a couple of times. No check engine light has come on

Just Started Having Problems On It’s On The Car Only Has 38,000 Miles

When headlight switch is set to automatically come on, the light will sometimes randomly turn off. No warning or indicator on the dash appears showing that they are off. Technicians are unable to reproduce the issue in the shop. Have recommended replacing the entire headlight switch on the turn signal stick.

Me and my family just returned home from the laundry mat and took 2 children inside our house and turned around for our belongings and clothing/bedding for the family as the wheels spun out being followed by a silver hyundaii. Just a matter of seconds to 2 minutes. The keys were not in the vehicle. 2 childrens carseats and almost ALL of my family's belongings were stolen inside of the vehicle. 2018 kia optima dark slate grey in color with dark tinted windows and sun strip at the top of windshield, black rims. CR 21077 IL LICENSE PLATE This seems to be an ongoing issue with kia and hyundaii vehicles being stolen and somehow im still not being offered a loaner vehicle with full coverage insurance

My car has been at the dealership since February 10th. The dealer has been giving me the run around. Didn’t have any transportation for over two months and car hasn’t moved since the day I dropped it off. I’m really getting impatient, as I am making monthly payments on a car that I can’t even use. Nearing four months and I’m totally lost on what to do. Thank you for any assistance

The headlights on my 2018 Kia Optima have been turning off and on randomly by themselves while in motion. Each time it's happened has been in different areas at different times of the night. The headlight switch is kept in the auto position most of the time. When the headlights turn off, the screen in the dash for the headlight function switches from auto to off by itself. Sometimes if the turn signal switch is jiggled the lights will come back on. Other times the headlight switch, located on the end of the turn signal switch, has to be turned to the on position to get the lights to turn on. The car has been in for service but each time the technician is unable to reproduce the fault. It is occurring more frequently and becoming a safety issue.

The electrical components connected to the headlights seem to be faulty. When lights are set to AUTO, the lights will turn off completely when switching on turn signal. At times the light will not come on at all when set to AUTO or On without cycle back to off.

Vehicle is making a noise when trying to accelerate. Have replaced all spark plugs and coil #4. It is making noise still and shaking. Coil has been switched and issues are reading fuel injector or air intake or electrical. Previous reading was head gasket... Only on spark plug 4 coil is it reporting an issue...All dealerships locally are booked to even get a diagnostic test.

While driving, car in motion, Front Passenger Seat belt Audio Warning Periodically goes off without reason. Indicating seat is occupied & seat belt needs putting on. When seat has been unoccupied / clear from any type of weight on seat to trigger sensor. Audio warning will continue until seat belt is latched over the empty seat. Local KIA Service Dept was informed & could neither confirm or deny its faulty behavior for it did not present itself during time of service. They said, wiring looked fine but did no further testing. To be honest they showed no interest into seeing any real importance for my concern for them to feel any further investigation was warranted. Its happened again twice since that service visit be it last incident Aug 7th. My concern is.... if there is faulty wiring or sensor signals being crossed somewhere, whats to say there is a passenger or no passenger in that seat, to ensure the correct signal is getting to the passenger side air bags of when to correctly deploy if an accident should happen with passenger in seat? This situ is only recent starting about a year a go. So something has changed from being fine for 2 yrs up to the last year that's now showing some kind of seat belt / sensor failure. I'm unfamiliar with how that wiring system works & linked within it for me know what other things I might need to pay more attn to, looking for other signs that could be saying is direct cause to the prob. Unsure if this a simple solution or is something that others are experiencing with this year & model car & poss be a Manufacturer Part Default

I HAVE 63,826 MILES ON MY 2018 KIA OPTIMA S AND I DROVE IT TO THE STORE AND ALL MY LIGHT ON THE DASH CAME ON WHEN I WOULD COME TO A STOP AND MY POWER STEERING WOULD GO OUT AND ABOUT CAUSE ME TO WRECK. I WAS TOLD THAT IT WAS MY ALTERNATOR BUT AFTER GETTING A NEW ALTERNATOR I THEN DROVE IT TO GET DINNER A FEW DAYS LATER WHEN THE SAME THING STARTED HAPPENING AGAIN AND MY POWER STEERING KEPT GOING OUT AGAIN. I HAVE TWO NEWBORN BABIES, A 5 YEAR OLD AND A 10 YEAR OLD IN THE VEHICLE WITH ME AND HAD I WRECKED WHEN THE POWER STEERING WENT OUT IT COULD HAVE BEEN A BAD SITUATION.

Mileage: 36,826

2018 KIA OPTIMA EX. SOMETIMES HESITATES WHEN TRYING TO START, UNTIL TODAY. ALL LIGHTS ON DASH LIT UP BUT NO IGNITION. I TRIED SEVERAL TIMES, THEN STEERING AND BRAKE PEDAL LOCKED UP AND I HEARD CLICKING NOISE. HAD SOMEONE JUMP MY BATTERY AND THE CAR STARTED UP, BUT WHEN I TURNED IT OFF, IT WOULD NOT START AGAIN. NOTHING WAS LEFT ON ALL NIGHT, CAR WAS LOCKED AND UNLOCKED WITH HANDLE. I AM CONTACTING THE DEALER THIS AFTERNOON TO SEE HOW THEY HANDLE THIS.

Mileage: 19,200

MY CAR SUDDENLY EXPERIENCE MAJOR ELECTRICAL ISSUES. I DROVE MY CAR TO THE STORE AND BACK HOME. I WENT BACK TO MY CAR AND IT STARTED WITH NO PROBLEM BUT MY DASH WAS FLASHING, MY BRAKE, STEERING, CHECK ENGINE, AIRBAG, ABS, AND TRACTION'S CONTROL INDICATORS CAME ON ALL AT ONCE. I WAS NOT ABLE TO SHIFT THE CAR INTO GEAR. I USED THE PARK RELEASE SHIFT TO PUT THE CAR IN GEAR AND THE CAR HAS NO POWER STEERING. BUT IT MOVES. I TOOK IT TO THE JEFFERY KIA IN ROSEVILLE,MI AND BASICALLY WAS TOLD THAT THEY DIDN'T KNOW WHAT WAS WRONG WITH CAR. THEY ASK ME HAD MY CAR BEEN STRUCK BY LIGHTNING! YOU CAN LOOK AT THE CAR AND SEE THERE HAS BEEN NO ACCIDENTS OR LIGHTNING STRIKES TO THE CAR. THEY WANTED TO CHARGE ME EXTRA MONEY TO KEEP THE CAR JUST TO TELL ME WHAT'S WRONG WITH IT. I KNOW THIS IS A DEFECT WITH THIS VEHICLE. I SEE THE EPD RECALL ON 2018 KIA OPTIMA BUT THEY ARE SAYING IT'S ONLY FOR HYBRIDS. WHICH IS FALSE THIS HAS TO BE HAPPENING TO ALL THE KIA OPTIMA MODELS.

WHILE DRIVING AT NIGHT LIGHTS WENT COMPLETELY OUT ON HIGHWAY WHILE IN AUTO MODE

Mileage: 45,325

I HAVE NEVER HAD ANY ISSUES WITH MY CAR, I GET MAINTENANCE AS SCHEDULED SO IT'S ODD THAT THIS IS EVEN HAPPENING. ON DECEMBER 6TH I WENT TO MOVE MY CAR. I CRANK THE CAR WITH NO PROBLEM. I NOTICED IT KIND OF HESISTATED SLIGHTLY, BUT CONTINUED ON WITH NO PROBLEM. WHEN I WENT TO PUT MY CAR IN REVERSE IN ORDER TO PARK IT STALLED AND ABOUT 5 OR 6 OF THE LIGHTS ON THE DASH CAME ON, THE STEERING WHEEL WENT HARD TO MANAGE/STEER AND AS 6 OTHER LIGHTS STARTED BLINKING, I COULD NO LONGER MANIPULATE MY WHEEL SO I ALLOWED THE CAR TO ROLL INTO THE SPOT BECAUSE I WAS ON A SLIGHT INCLINE AND PUT IT IN PARK. THE MOMENT I DID THAT THE CAR CUT OFF. IT WOULD NOT TURN OVER, IT WOULD NOT DO ANYTHING BESIDES CLICK WHEN I TRIED TO CRANK THE CAR AGAIN. I EVENTUALLY ASKED SOMEONE FOR A JUMP AND MANAGED TO MAKE IT HOME. THE NEXT DAY I GOT UP AND DROVE AS I NORMALLY WOULD AND THATS WHEN THE ELETRIC POWER STEERING WARNING LIGHT CAME ON. WHEN THAT LIGHT COMES ON THE CAR BECOMES HARD TO MANEUVER. THANKFULLY THAT TIME IT WENT OFF AND PROCEEDED TO DRIVE AS IT WOULD NORMALLY. THIS ISSUE HAPPENS UNEXPECTEDLY WITHOUT ANY WARNING. SO AT ANY MOMENT I COULD BE DRIVING AND THE CAR CAN STOP ON ME. I HAVE 4 KIDS AND LIVE IN A REALLY BUSY AREA SO EVEN THE THOUGHT OF THIS HAPPENING HAS ME SECOND THINKING EACH TIME I HAVE TO MOVE MY CAR!! I'VE SEEN MORE THAN ONE OF THE SAME COMPLAINT AND I NOTICE OUR VIN #'S ARE SIMILAR SO SOMETHING SHOULD REALLY BE DONE ABOUT THIS AS IT SEEMS THIS IS A TREND WITH THE YEAR, MAKE, AND MODEL OF THIS CAR.

Mileage: 42,100

HELLO I AM NYCHOLE AND IN OCTOBER OF 2017 I PURCHASED A BRAND NEW 2018 KIA OPTIMA . NEVER REALLY HAD ANY ISSUES WITH IT UNTIL FRI NOV 22. AS I WAS LEAVING FROM WORK MY CAR DID A VERY ABRUPT JERK THAT I ACKNOWLEDGED BUT DIDN'T THINK ANYTHING OF IT BECAUSE MY GAS LIGHT HAD JUST CAME ON. BUT TODAY WHICH IS SUNDAY MY CAR'S EPS (ELECTRIC POWER STEERING) LIGHT FLASHED. WEIRDED OUT I LOOK AT THE MANUAL IN THE GLOVE COMPARTMENT. AS I EASED INTO MY APARTMENT COMPLEX THE CAR DID THAT SAME JERK, THE STEERING WHEEL WENT HARD TO MANAGE/STEER AND 6 OTHER LIGHTS STARTED BLINKING( PARKING BREAK LIGHT,EPB LIGHT ,ABS LIGHT,ESC LIGHT ,BATTERY CHARGE LIGHT, AND THE MASTER MALFUNCTION LIGHT) . I COULD NO LONGER MANIPULATE MY WHEEL SO I PULL FORWARD ONTO A OPEN SPOT AND PUT IT IN PARK. THE MOMENT I DID THIS THE CAR CUT OFF. IT WILL NOT TURN OVER, IT WILL NOT DO ANYTHING BESIDES TICK. I HAVE BEEN GREAT WITH MAINTENANCE BECAUSE IT WAS EITHER FREE OR DIRT CHEAP SO I ALWAYS TOOK IT TO THE DEALERSHIP. I HAVE READ MORE REVIEWS OF PEOPLE GOING THROUGH SIMILAR THINGS. JUST IMAGINE IF I HAD MY CHILD IN THE CAR, ON THE INTERSTATE AND COULD NO LONGER CONTROL MY STEERING WHEEL OR THE CAR JUST DYING MID DRIVE ON THE INTERSTATE HOW DANGEROUS THIS ISSUE IS. MY CAR IS BASICALLY 3 YEARS OLD AND HAS LESS THAT 50 K. IT HAS NEVER BEEN WRECKED , TOWED OR DAMAGED STILL PRACTICALLY NEW. I HAVE ALSO READ SIMILAR RECALLS ABOUT ELECTRONIC ISSUES THAT ARE ONLY RELEVANT TO THE HYBRIDS . THE RECALL SEEMS SIMILAR.

Mileage: 57,000

TL* THE CONTACT OWNS A 2018 KIA OPTIMA. WHILE REVERSING THE VEHICLE, THE REAR AND SIDE SENSORS FAILED TO IDENTIFY TWO PEOPLE WALKING PAST. THERE WERE NO WARNING INDICATORS ILLUMINATED. THE VEHICLE WAS TAKEN TO SUNSET KIA OF AUBURN (3401 AUBURN WAY N, AUBURN, WA 98002, (855) 474-9626) WHO STATED THAT THE SENSORS WERE WORKING AS DESIGNED. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS NOT CONTACTED. THE FAILURE MILEAGE WAS 14,356.

Mileage: 14,356

TAKARA RECALL VEHICLE POWER DOWN WHILE I WAS DRIVING 45 MPH ON A CITY STREET THE CAR WAS STATIONARY IN MOTION THEN POWERED BACK UP WITHOUT ME TURNING THE IGNITION.WAS A VERY SCARY EXPERIENCE

Mileage: 12,098

THIS HAS OCCURRED ON 3 TIMES SO FAR. I WAS AT A GAS STATION FILLING UP THE TANK, THE KEY WAS IN THE IGNITION, THE CAR WAS IN PARK, THE ENGINE WAS RUNNING, AND MY CAR DOOR WAS CLOSED. WHEN I FINISHED GETTING GAS, I TRIED TO OPEN THE DRIVER SIDE DOOR AND IT WAS LOCKED. ALL DOORS WERE LOCKED. I WAS 20 MILES FROM HOME FORTUNATELY SOMEONE WAS AT HOME TO BRING A SPARE KEY FOR ME TO OPEN THE TRUNK, PUSH THE REAR PASSENGER SEATS DOWN AND CLIMB THRU TO THE FRONT TO TURN THE IGNITION OFF AND UNLOCK THE DOOR. THE SAME SCENARIO OCCURED THIS PAST WEEK WHEN I HAD GONE OUTSIDE TO WARM UP MY CAR BY TURNING ON THE DEFROST FOR THE FRONT AND BACK WINDOWS. ONCE AGAIN, THE ENGINE WAS RUNNING AND I CLOSED THE DOORS. ONCE THE CAR WAS WARM, I TRIED TO OPEN THE DOOR AND IT WAS LOCKED. I HAD TO GO IN THE HOUSE TO GET THE OTHER SET OF KEYS, OPEN THE TRUNK PUSH THE BACK SEATS DOWN AND CLIMB THRU THE TO THE FRONT, TURN OFF THE IGNITION AND UNLOCK THE DOOR. THIS LAST OCCURENCE WAS ONCE AGAIN AT A GAS STATION, THIS TIME IT WAS LATE AT NIGHT, IT WAS 20 DEGREES OUTSIDE AND HAD TO WAIT FOR SOMEONE FROM MY HOUSE BRING THE SPARE KEYS. THE QUESTION I HAVE FOR MYSELF IS, WHAT AM I GOING TO DO IF NO ONE IS AT MY HOUSE TO BRING THE EXTRA KEY. SURELY, I DONT PLAN TO BRING TWO SETS OF KEYS WITH ME. EVERYTIME I'VE TAKEN IT TO THE KIAOFDAYTON SERVICE CENTER, I AM TOLD THEY CANNOT RECREATE THE ISSUE. I'VE TAKEN IT TO THE DEALERSHIP TWICE. IT'S VERY FRUSTRATING. IN EVERY INSTANCE THE CAR WAS IN PARK, THE ENGINE WAS RUNNING, AND THE DOORS WERE UNLOCKED WHEN I HAD EXITED THE VEHICLE. WHEN I ATTEMPTED TO GET BACK IN, I COULD NOT BECAUSE THE DOORS HAD LOCKED BY THEMSELVES.