2011 Hyundai Sonata Electrical System Problems

My 2011 Hyundai Sonata experienced a flashing check engine light and entered limp mode (vehicle cannot accelerate), displaying diagnostic code P1326. This code is associated with Hyundai’s Knock Sensor Detection System (KSDS), which was installed as part of a recall-related campaign to detect engine bearing failure in Theta II engines. The vehicle previously had its engine replaced under recall due to known defects involving connecting rod bearing failure. The current condition renders the vehicle unsafe to operate, as it is limited in power and may stall or fail unexpectedly. The system is designed to detect potential engine failure, which is a known safety issue. Despite this, the dealership has not completed proper diagnostic procedures related to the KSDS system and potential engine failure. The vehicle has been out of service for approximately one month without resolution. This appears to involve a failure of a recall-related safety system (KSDS) and/or a recurring engine defect that Hyundai has previously acknowledged. My biggest concern is that they are diagnosing this issue as an electrical defect rather than the engine itself (which the system is design to warn about) in order to avoid having the repairs covered under the warranty that originated due to the class action lawsuit, and this component was only created and provided to consumers with no charge in order to protect the company from having to continue replacing defective engines

The vehicle experiences a recurring defect where the brake light turns on suddenly and the engine shuts off while driving. The failure appears related to the braking system (brake switch circuit), electrical system (CAN-bus/ECU communication), and engine control (shutdown/stall). The system remains installed and is available for inspection upon request. The shutdown poses a serious safety risk, including possible rear-end collision or loss of power in traffic. The problem has occurred multiple times. The dealership inspected the vehicle briefly but failed to diagnose or document the defect and returned the vehicle within hours, stating “it shouldn’t be a problem,” even though the issue continues. Hyundai has refused to provide recall documentation or authorize a re-inspection. The only warnings prior to shutoff are the sudden activation of the brake warning light just before the engine cuts off.

2011 Hyundai Sonata had a Theta ii engine replaced in September 2024 after engine failure. Hyundai paid for the engine through the extended warranty on the theta engines. Check engine light is still illuminated after new engine and after multiple visits to the dealership, they say the wiring harness is bad. Contacted Hyundai Corporate who said they will not pay for anymore warranty repairs, even though the wiring harness was damaged from the bad engine or during the replacement. From my understanding, it is dangerous to drive a car with a bad wiring harness due to fire risk, loss of power, or loss of safety components.

The vehicle just died out of nowhere. Would not start back up. Has a clicking noise when trying start and then had a burning smell.

Electrical needs to be reconnected a reprogrammed. Steering wheel horn doesn’t blow.

The contact owned a 2011 Hyundai Sonata. The contact stated that while her husband was driving at 60 MPH, the instrument panel started flickering, the engine started to rev, and the vehicle stalled. The vehicle veered to the side of the road and was parked. The contact then noticed that there was smoke coming from the vehicle and proceeded to open the hood of the vehicle. Soon after, flames were discovered coming from under the vehicle. The contact and her husband removed all personal items and watched from a safe distance. The fire department arrived at the scene however the vehicle was entirely consumed by the fire. The ambulance also arrived at the scene however no medical attention was provided since there were no physical injuries. The contact and her husband sustained emotional distress due to the incident. A police report was filed. The vehicle was destroyed. The manufacturer was not made aware of the failure. The failure mileage was unknown.

Car spontaneously caught fire while turned on. First smoke started coming from under the hood. Within three - five minutes, the car erupted in flames followed by a minor explosion that burned more than half of the car causing a total loss.

On [XXX], I smelled a chemical burning smell. We searched the house for about 5 minutes and finally went to the garage. As my husband opened the garage door he said the car is on fire. I looked and smoke was pouring out of the inside. He ran, opened the door and flames came bursting out. He immediately took off to get the fire extinquisher from the kitchen and I called 911. The fire department came and put the flames out. Upon inspection, the dashboard had a fire and the extreme heat had melted the entire dash. The fire chief and my husband were trying to figure out what had happened. The car was not running at the time. A little earlier, my husband had an air compressor plugged into the cigarette lighter. When he finished filling a tire, he unplugged the compressor, put the compressor in the car on the floor and turned the car off. Then later, as I described there was a fire. My husband and the fire chief inspected the engine which had no damage. The were specifically looking for the fuses. All fuses were in tact. In researching I discovered the the Hyundai Sonata had issues and new about the problems. We purchased the car in March and were not aware of any recalls, nor were the previous owners. I have spent the last 6 weeks in communication with Hyundai who led me on a wild goose chase and has refused to take responsibility for the fire. The are trying to blame in on the compressor which was not even plugged in. I was made aware of several class action law suits, but have not been able to find any information. I have kept all communication with Hyundai and have requested the recorded phone conversations also. The car is still in my driveway. Obviously all the electrical is destroyed and not fixable. I was trying to avoid lawyers and just get Hyundai to own up to the problem and take responsibility to pay what I paid for the car. I can get copies of all email communication. I attached the final email received yesterday. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Engine leaks/burns oil too frequently. Every other week I’m continuously having to put oil to refill levels. Also electrical system for turn signals is always going in and out. Sometimes it works and sometimes it doesn’t. Safety hazard because other vehicles can’t tell that I’m turning.

I was gifted the car for graduation and immediately my brakes weren’t working right my interior electrical stopped working and my window switches stopped working as well as my lights for my car all went out including the brake lights changing the bulbs didn’t help and my check engine light stays on at all times.

I [XXX] purchased the vehicle from a dealership Mr. T’s world test drive the car was fine left the dealership had to go back he change the brake lights made it back left to go to the store the next day had to pull over they had smoke coming from under the hood open the hood up the wires was on fire INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

My car airbag light came on. I called the dealership about the remedy that was already recalled under campaign number 18V137000 because my last visit I got told by the dealership that my ACU was bad for the car and that it was going to cost me upwards of $2000 to replace and the dead was no recall on my vehicle and then called corporate and they had told me that this had been taken care of back in 2016 when I did not on the vehicle this time in the second owner and that basically they would not cover to fix this issue and that any warranty that was extended ran out when I only had purchased the vehicle in November 2020 so now they are unwilling to fix the issue because they had stated that it was already previously fixed with the previous owner and then I could either basically pay to get it fixed or they weren’t gonna do anything about it I feel my safety at risk because in the event of crash airbags will not deploy and basically that they would not fix the problem even though it is under a National recall, and my car was manufactured within the manufacturing dates of the recall I do not feel safe driving this vehicle, and I also do not feel that I have to pay for that has been nationally recalled

Prior to my trip I checked all fluids, and all was good levels. Car was traveling on improved interstate at posted highway speed. As I was passing another vehicle my vehicle lost power and I was forced to cross lanes in traffic to get to shoulder. There were no prior warnings or lights before my vehicle lost power. I opened my hood and saw the radiator coolant boiling over in reservoir and the top hose was collapsed. Had the vehicle towed home. I checked and replaced the thermostat however found that the engine would not turn over and the starter failed.

The contact owns a 2011 Hyundai Sonata. The contact stated that after the manufacturer performed Service Campaign 993 (Inspect & Anti-Theft Software Upgrade) the vehicle failed to shutoff as needed. Additionally, the alarm was activated while starting the vehicle. The contact disconnected the battery to shutoff the vehicle. The vehicle was taken to the dealer, where pliers were used to remove the key fob and a second key was used to restart the vehicle; however, the failure recurred. The vehicle was not diagnosed or repaired. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 112,000.

When I have my headlights turned on, and am driving my headlights flicker on and off. It mostly happens when I use the turn signal, but not always. sometimes it happens when I hit bumps. The headlights and the dash lights all go out when this happens, it usually lasts from 1 to 20 seconds at a time. I have taken it to my local garage(straight and clear) and they tested all electrical components and replaced the alternator and I still have the issue. They looked it up and determined that this is a known issue with the Hyundai Sonata, and one of the modules needs replaced in the steering column. This is a major safety issue because my headlights go out when driving and could cause and accident, and depending on the exact issue of the module it could cause a fire. There are no warning lights, just the lights go on and off. I will be getting the car repaired around November 9th 2023, because I need my car to be safe, and can submit my invoice at that time if this becomes a recall.

Engine seized at 87337 miles today. Fuel gauge wrong. Left us stranded on the interstate for 3 hours. Couldn't get it off highyway without pushing. No warning or lights before engine blew. All fluid levels correct. Silver Rock and Carvana refuse repair.

My brake lights constantly go out new bulbs don't work either...it sems to be a malfunction in the wiring for the lights. The seatbelt on driver side will not latch no matter what. All electrical has issues, dash will go in and out as well as radio and heating/ac lights.

THE ALTERNATOR AND BATTERY OF THIS VEHICLE HAS BEEN SWITCHED AT LEAST 3 TIMES. PURCHASED NEW AND ALL, YET THE CAR KEEPS GETTING DRAINED AND LEFT POWERLESS. SOMETHING IS DRAINING THE ENERGY OF THE VEHICLE AND THE ROOT TO THE PROBLEM IS NOT KNOWN.

I have had replaced my taillight bulbs 8 times in the last year. They keep blowing out and getting so hot they melt the taillight assembly. I replaced the whole assembly a couple months ago and it is already melted so bad the light bulb will not fit properly or stay in place. This is a fire hazard and also a safety hazard as my taillights quit working at anytime.

Took vehicle in for recall due to check engine light flashing on March 26,2023 .Received a call from dealership that car was ready March 28,2023 upon driving home car overheats. Call dealership to relay problem was advised to bring vehicle back. Had vehicle towed back to dealership at my own expense. Two weeks later I get a call stating that it was the radiator and that they would fix it and get it back to me . Two weeks after not hearing from dealership I called do an update to my surprise now it the engine is bad. So I ask the service manager where do we go from here. He proceeds to tell me that it’s one of those things where the recall didn’t help but hurt my engine. Then he proceeds to say I would have to give the dealership $2,000 dollars to fix the problem they caused. So here we are 4 months in and I still do not have a vehicle nor do I know who is responsible for fixing it.