2015 Hyundai Sonata Hybrid Problems

The Hybrid system kept crashing ! Triggering the auto theft and would not connect to fob , told it was immobilzer, and/or shortage in EV battery!!!

Component Involved: Hybrid Propulsion System High Voltage Battery / EV Battery Electrical System Power Train Incident Summary: I am reporting a serious and repeated safety defect involving my 2015 Hyundai Sonata Hybrid. This vehicle has experienced three separate incidents where warning messages related to the EV/hybrid battery system appeared, followed by a sudden loss of forward propulsion. During these events, the vehicle would not move properly or lost the ability to accelerate safely. This defect creates a major safety hazard because it can occur while driving, increasing the risk of being rear-ended, stranded in traffic, collision, injury, or property damage. I transport my small children in this vehicle and no longer feel it is safe. Detailed Timeline: Initial Incident: Vehicle displayed warning messages involving the EV/hybrid battery system and lost the ability to move forward properly. Vehicle had to be shut off and restarted. Independent Mechanic Inspection: Vehicle was inspected by an independent mechanic who advised the hybrid battery system likely needed repair or replacement and recommended service through Hyundai dealership. Dealer Visit #1 – Stew Hansen Hyundai (3/18/2026): Vehicle was taken to authorized Hyundai dealer for diagnosis. Dealer stated they could not duplicate the issue and no repair was made. Second Failure: After release from dealer, same dangerous loss-of-power condition occurred again, resulting in towing and additional inconvenience. Dealer Visit #2 – Stew Hansen Hyundai (4/8/2026): Vehicle returned to dealer for same issue. Dealer performed software update and stated this should correct problem. Dealer advised vehicle had been driven approximately 40 miles and was safe to release. Third Failure (4/12/2026 approx.): Only two days after picking vehicle up on 4/10/2026, same warning messages and propulsion failure occurred again. Safety Concern: This repeated loss of propulsion without warning is extremely dangerous.

Idle and warning to not drive, 2025 very subtle cut off now full warning

The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving 5 MPH and making a left turn, the vehicle made an abnormal knocking sound. The contact stated that upon pulling into an apartment complex parking lot, the contact noticed that there was smoke coming out from underneath the hood. There was no warning light illuminated. The contact immediately parked and exited the vehicle. The contact stated that upon opening the hood, the contact noticed a small fire and was able to extinguish the fire with a water bottle. The contact was able to push the vehicle into a parking space with the assistance of her son. There was no injury sustained. No police report was filed. The vehicle was towed to an independent mechanic, where it was diagnosed that a fluid leak from an unknown hose had caused the fire, and there was a hole in the engine block. The contact also stated that there was a puddle of fluid on the ground. The vehicle was not repaired. The contact became aware that the VIN was included in NHTSA Campaign Number: 23V651000(Service Brakes, Hydraulic), which the contact related to the failure. The dealer and the manufacturer were not notified of the failure. The failure mileage was approximately 115,395.

We pulled up at Hillgreen circle Cockysville MD To drop my boyfriend off at his apartment. I went to pull in the parking spot.I went to put the car into park and it had no brakes. I was slamming them and pumping them. It excellerated and took off. Jumped the curb,went down the hill and into the apartment building. A red light had came on the dash, right before it took off. Seemed like it was changing to gas or the electric mode,or the other way around. The airbag on the passenger side came out deflated,and filled with smoke going into the car. He was the belted front passenger and his elbow went in to the front window. You can tell by looking at it,the hole and spidered around it. He broke his right elbow. It is available anytime at the moment. It's at Hyundaii in Glen burnie. I need to get it to state farms lot,to get the Kelly blue book value. We look forward to hearing from you

The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving 5 MPH and making a left turn, the vehicle made an abnormal knocking sound. The contact stated that upon pulling into an apartment complex parking lot, the contact noticed that there was smoke coming out from underneath the hood. There was no warning light illuminated. The contact immediately parked and exited the vehicle. The contact stated that upon opening the hood, the contact noticed a small fire and was able to extinguish the fire with a water bottle. The contact was able to push the vehicle into a parking space with the assistance of her son. There was no injury sustained. No police report was filed. The vehicle was towed to an independent mechanic, where it was diagnosed that a fluid leak from an unknown hose had caused the fire, and there was a hole in the engine block. The contact also stated that there was a puddle of fluid on the ground. The vehicle was not repaired. The contact became aware that the VIN was included in NHTSA Campaign Number: 23V651000(Service Brakes, Hydraulic), which the contact related to the failure. The dealer and the manufacturer were not notified of the failure. The failure mileage was approximately 115,395.

TL* THE CONTACT OWNS A 2015 HYUNDAI SONATA HYBRID. WHILE DRIVING VARIOUS SPEEDS AND ATTEMPTING TO BRAKE, THE VEHICLE ACCELERATED. THE CONTACT DEPRESSED THE BRAKE PEDAL MULTIPLE TIMES AND WAS ABLE TO STOP THE VEHICLE. THERE WAS NO WARNING INDICATOR ILLUMINATED. IN ADDITION, THE VEHICLE INTERMITTENTLY FAILED TO ACCELERATE WHEN THE ACCELERATOR PEDAL WAS DEPRESSED. THE FAILURES RECURRED SEVERAL TIMES. THE VEHICLE WAS TAKEN TO JIM CLICK MAZDA AUTO MALL (877-888-2760, LOCATED AT 700 W AUTO MALL DR, TUCSON, AZ 85705), BUT THE FAILURES COULD NOT BE DIAGNOSED OR DUPLICATED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURES. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS NOT PROVIDED.

TRANSMISSION ACTS LIKE IT IS SLIPPING AND SHIFTS ABNORMALLY IN FORWARD AND REVERSE, DRIVER WINDOW UP/DOWN BUTTON DOESN'T WORK CORRECTLY IT ONLY MAKES THE WINDOW GO UP 1/4 OF THE WAY SO YOU HAVE TO LET GO AND PRESS IT AGAIN. THE RADIO KEEPS SHOWING AND ERROR MESSAGE WAITING TO GET INTO THE DEALER

TL* THE CONTACT OWNS A 2015 HYUNDAI SONATA HYBRID. WHILE DRIVING VARIOUS SPEEDS AND ATTEMPTING TO BRAKE, THE VEHICLE ACCELERATED. THE CONTACT DEPRESSED THE BRAKE PEDAL MULTIPLE TIMES AND WAS ABLE TO STOP THE VEHICLE. THERE WAS NO WARNING INDICATOR ILLUMINATED. IN ADDITION, THE VEHICLE INTERMITTENTLY FAILED TO ACCELERATE WHEN THE ACCELERATOR PEDAL WAS DEPRESSED. THE FAILURES RECURRED SEVERAL TIMES. THE VEHICLE WAS TAKEN TO JIM CLICK MAZDA AUTO MALL (877-888-2760, LOCATED AT 700 W AUTO MALL DR, TUCSON, AZ 85705), BUT THE FAILURES COULD NOT BE DIAGNOSED OR DUPLICATED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURES. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS NOT PROVIDED.

WAS DRIVING ABOUT 25 MPH AND IT SENT WARNING LIGHTS AND STUTTERED AND DIED IN FRONT OF RAILROAD TRACKS. VERY LUCKY IT DIDN'T DIE ON THE TRACKS.

The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed, the message "Turn off the Engine Immediately" was displayed. Several unknown warning lights were illuminated. The vehicle was taken to the dealer, who was unable to duplicate the failure. The vehicle was not repaired. Later, the contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to pull to the shoulder of the roadway, where the vehicle failed to restart with several unknown warning lights illuminated. The vehicle was towed back to the dealer, who then diagnosed failures with the ABS and transmission. The vehicle was repaired, but the failure reoccurred. The manufacturer was notified of the failure but provided no assistance. The failure mileage was unknown.

The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated that while driving at an undisclosed speed, several unknown warning lights were illuminated. The contact stated that while depressing the brake pedal, the brake pedal went to the floorboard. The contact stated that the warning light to turn off the vehicle was illuminated. The contact turned the vehicle off and the vehicle failed to restart. The vehicle was towed to the dealer; however, the dealer refused to service the vehicle. The vehicle was then towed to the residence. The vehicle was towed to another Hyundai dealer where the vehicle was diagnosed with a failed transmission and battery. The contact was informed that the transmission and battery needed to be replaced. The vehicle was repaired. The contact stated while driving away from the dealer, she heard an unusual knocking sound coming from the engine compartment. The vehicle was taken back to the dealer. The service technician accompanied the contact for a test drive and confirmed the knocking coming from the engine compartment. The contact was informed that the new transmission that was installed was defective, and the transmission needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 74,680.

Idle and warning to not drive, 2025 very subtle cut off now full warning

I HAD TWO CASE NUMBERS WITH HYUNDAI RELATED TO MY BRAKES AND FUEL EFFICIENCY; THE FIRST WAS HYUNDAI CONSUMER AFFAIRS CASE#: 12894630 AND THE SECOND WAS HYUNDAI CONSUMER AFFAIRS CASE#: 15512885. BOTH CASES WERE CLOSED PRIOR TO ME HAVING ANY SAY IN THE DECISION (EMAIL/PHONE RECORDS SHOW THIS). AFTER MY BRAKING UNIT FAILS FOR THE SECOND TIME AND I NOTICED A SIGNIFICANT DROP OFF IN FUEL PERFORMANCE (MPG), I ASKED FOR ANOTHER HYUNDAI REP TO TEST MY FUEL CONSUMPTION. WHEN THE RESULTS PROVED TO BE BETTER THAN I HAD EVER SEEN MY CAR PERFORM, EVER, I ASKED FOR THE REST SPECKS. THIS WAS ESCALATED TO HYUNDAI CORPORATE, WHO RESPONDED 'UNFORTUNATELY YOUR CASE MANAGER CANNOT PROVIDE ANY TSB'S BECAUSE IT IS PROPRIETARY INFORMATION. AS FAR AS WARRANTY EXTENSION, REGRETTABLY THAT IS NOT AN OPTION. HOWEVER, IF YOU WERE TO HAVE BRAKE CONCERNS OUTSIDE OF WARRANTY, HYUNDAI WILL REVIEW FOR GOODWILL IF THE PROBLEM IS SOMETHING THAT WAS PREVIOUSLY REPAIRED UNDER WARRANTY.' THIS ANSWER FAILED TO CONSIDER THE MILEAGE I WAS ALREADY LOSING IN MY HYBRID WHICH PERFORMED WORSE THAN A NON-HYBRID MODEL WHENEVER THE BRAKES WERE FAILING. I MADE GOOD FAITH EFFORTS TO REPORT MY PROBLEMS IN THE HOPE HYUNDAI WOULD RESOLVE THEM.

The contact owns a 2015 Hyundai Sonata Hybrid. The contact stated while stopped in traffic, the vehicle independently jolted with a message indicating a Hybrid System safety failure. Additionally, there was a message to stop driving the vehicle with an alarm sounding. The contact veered to the side of the road. The contact was able to continue driving. The contact received notification of NHTSA Campaign Number: 23V651000 (Service Brakes, Hydraulic) the following day; however, the part to do the recall repair was not yet available. The contact stated that the failure recurred while driving. The contact veered to the side of the road. The vehicle was then taken to an independent mechanic, where it was test-driven; however, the mechanic was unable to duplicate the failure. The local dealer was contacted and informed the contact that the earliest availability was on December 23, 2023. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 97,500. VIN tool confirms parts not available.

TL* THE CONTACT OWNS A 2015 HYUNDAI SONATA HYBRID. THE CONTACT STATED THAT WHILE DRIVING AT 55 MPH, THE VEHICLE STALLED AS THE "HYBRID SYSTEM WARNING, SAFELY STOP AND DO NOT DRIVE" WARNING MESSAGE APPEARED ON THE INSTRUMENT PANEL. DUE TO THE FAILURE, THE VEHICLE BEHIND HER ATTEMPTED TO AVOID HITTING HER; HOWEVER, THE VEHICLE BEHIND THAT VEHICLE COLLIDED INTO HIS WHICH CAUSED AN ACCIDENT. THE CONTACT WAS THEN FORCED TO RESTART THE VEHICLE IN THE MIDDLE OF TRAFFIC AND WAS ABLE TO RESUME NORMAL DRIVING. THE CONTACT THEN TOOK THE VEHICLE TO BUD CLARY AUBURN HYUNDAI (2807 AUBURN WAY N, AUBURN, WA 98002) WHERE THEY WERE UNABLE TO DUPLICATE THE FAILURE. SHE ALSO TOOK THE VEHICLE TO AN INDEPENDENT MECHANIC WHO WAS ALSO UNABLE TO DUPLICATE THE FAILURE ALSO. THE CONTACT STATED THAT THE FAILURE HAD OCCURRED TWICE SINCE THE INITIAL FAILURE. THE MANUFACTURER HAD YET TO BE NOTIFIED OF THE FAILURE. THE VEHICLE HAD YET TO BE REPAIRED. THE FAILURE MILEAGE WAS 152,000.

TL* THE CONTACT OWNS A 2015 HYUNDAI SONATA HYBRID. WHILE DRIVING 20 MPH, THE FRONT PASSENGER SIDE COIL SPRING FRACTURED AND EXITED THROUGH THE FRONT PASSENGER TIRE. THERE WERE NO WARNING INDICATORS ILLUMINATED. THE LOCAL DEALER WAS NOT CONTACTED. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS CONTACTED AND STATED THAT THE VEHICLE WAS NOT COVERED UNDER WARRANTY. CASE NUMBER: 15697010 WAS PROVIDED AND THE CONTACT WAS REFERRED TO A DEALER. THE CONTACT STATED THAT THE FAILURE WAS SIMILAR TO NHTSA CAMPAIGN NUMBER: 15V629000 (SUSPENSION). THE FAILURE MILEAGE WAS 69,000.

PUSH BOTTON START DOESNT A LOT OF THE TIME SEVERAL TIMES A WEKK START THE ENGINE. ALSO, THE SUSPENSION IS TERRIBLY ROUGH. YOU CAN FEEL EVERY BUMP!

TL* THE CONTACT OWNED A 2015 HYUNDAI SONATA HYBRID. THE CONTACT STATED THAT WHILE STOPPED, THE VEHICLE WAS REAR ENDED BY ANOTHER VEHICLE. THE CONTACTED STATED THAT THE FRONT SEAT PASSENGER SUSTAINED INJURIES TO THE LEFT SHOULDER, NECK AND BACK WHICH REQUIRED MEDICAL ATTENTION DUE TO THE SEAT BELT RETRACTING TOO TIGHT. THE DRIVER ALSO SUSTAINED INJURIES TO HIS NECK AND BACK WHICH ALSO NEEDED MEDICAL ATTENTION. THE CONTACT STATED THAT ANY INJURIES OF THE OTHER VEHICLE WERE UNKNOWN. THE CONTACT STATED THAT THE AIR BAGS DID NOT DEPLOY AND NO WARNING LIGHTS WERE ILLUMINATED. A POLICE REPORT WAS FILED. THE VEHICLE WAS REPAIRED. THE CONTACT ALSO MENTIONED THAT ON SEVERAL OCCASIONS WHILE STOPPED, THE VEHICLE WOULD JERK WITH NO WARNING. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED AS THE CONTACT TRADED-IN THE VEHICLE AT ROUND ROCK HYUNDAI DUE TO THINKING THERE WAS A FAILURE WITH THE SEAT BELTS AS THEY WOULD RETRACT AGGRESSIVELY. THE MANUFACTURER WAS MADE AWARE OF THE FAILURES. THE CONTACT MENTIONED THAT THE VEHICLE HAD TWO EXTENDED WARRANTIES BUT THE FAILURES WERE UNKNOWN. THE FAILURE MILEAGE WAS 10,000.

THIS VEHICLE HAS ELECTRIC POWER STEERING. WHEN DRIVING ON THE HIGHWAY, IT IS IMPOSSIBLE TO KEEP THE CAR TRACKING STRAIGHT. IT IS NOT A TIRE ISSUE, NOR IS IT A CROWN IN THE ROAD ISSUE. THE VEHICLE MUST CONTINUOUSLY BE CORRECTED TO KEEP IN A STRAIGHT LINE. WINDY CONDITIONS CAUSE THE VEHICLE TO RADICALLY RESPOND TO ADJUSTMENTS, SO DOES A LARGE TRUCK IN FRONT OF MY VEHICLE. HYUNDAI STATES THERE IS NOTHING WRONG WITH MY VEHICLE. IF YOU GO ONLINE, THERE ARE THOUSANDS OF HYUNDAI CUSTOMERS WITH THE SAME ELECTRIC STEERING ISSUES MIMICKING MY ISSUES TO A TEE, AND THEY SAY HYUNDAI IS "STONEWALLING" THEM, TELLING THEM THERE IS NOTHING WRONG, THERE IS LEARNING CURVE DRIVING AN ELECTRIC POWER STEERING VEHICLE. HOW CAN THOUSANDS OF HYUNDAI CUSTOMERS HAVE THE SAME PROBLEM? WHY ISN'T YOUR ORGANIZATION LOOKING INTO TO THIS? THERE WAS A RECALL OF THE ELECTRIC POWER STEERING ON HYUNDAI VEHICLES IN 2007. DOESN'T THAT SHOW YOU THAT THEY HAD A PROBLEM, AND MAYBE THEY ONLY PUT A BANDAID ON AN OPEN WOUND? FINALLY, I WAS DRIVING TO WORK ON ROUTE 295 SOUTH IN NJ 3 WEEKS AGO. A NJ STATE TROOPER FOLLOWED BEHIND ME FOR 2 MILES THEN PULLED ME OVER. I ASKED "WHAT WAS THE PROBLEM"? THE OFFICER SAID WHILE FOLLOWING YOU THERE WASN'T ANY TIME YOU WERE ABLE TO STAY IN YOUR LANE. I TOLD ABOUT MY ISSUE WITH ELECTRIC POWER STEERING AND SHOWED HIM THE E-MAILS TO HYUNDAI. HE MADE ME GET OUT OF MY CAR, AND GAVE ME A SOBRIETY TEST. I PASSED OF COURSE. THEN HE ASKED IF HE COULD INSPECT THE INSIDE OF MY VEHICLE. I COULDN'T BELIEVE IT! HE WAS LOOKING FOR ALCOHOL OR DRUGS. OF COURSE THERE WAS NONE, AND HE GAVE ME A WARNING. HYUNDAI TO THIS DAY REFUSES TO ACKNOWLEDGE ANY PROBLEM WITH THERE ELECTRIC POWER STEERING. I DON'T WANT TO ENDANGER MYSELF OR ANYBODY ELSE WITH THIS DANGEROUS VEHICLE. PLEASE LOOK INTO MY COMPLAINT, AND THE THOUSAND OF OTHERS WHO ARE ALSO DEALING WITH THIS ISSUE

We pulled up at Hillgreen circle Cockysville MD To drop my boyfriend off at his apartment. I went to pull in the parking spot.I went to put the car into park and it had no brakes. I was slamming them and pumping them. It excellerated and took off. Jumped the curb,went down the hill and into the apartment building. A red light had came on the dash, right before it took off. Seemed like it was changing to gas or the electric mode,or the other way around. The airbag on the passenger side came out deflated,and filled with smoke going into the car. He was the belted front passenger and his elbow went in to the front window. You can tell by looking at it,the hole and spidered around it. He broke his right elbow. It is available anytime at the moment. It's at Hyundaii in Glen burnie. I need to get it to state farms lot,to get the Kelly blue book value. We look forward to hearing from you

ON SAT, OCT 1, AT ABOUT 1 PM I WAS ABOUT TO COMPLETE PARKING THE VEHICLE IN THE PARKING LOT OF THE HUNTINGTON BEACH BRANCH OF CHASE BANK. I FORTUNATELY SELECTED A SITE ON FRONT OF A PLANTER SECTION WITH BUSHES, AS OTHERWISE THERE COULD HAVE BEEN INJURIES OR PROPERTY DAMAGE. I WAS ALMOST STOPPED AND WAS ABOUT TO PUT THE GEAR IN PARK, THE CAR SUDDENLY REVVED UP THE ENGINE AND ACCELERATED VIOLENTLY AND WITH GREAT FORCE, PROPELLING THE CAR OVER THE CEMENT CURBS OF THE PLANTER AND LANDED IN THE BUSHES. THE CAR COULD NOT BE REVERSED OUT OF THE BUSHES AS THE WHEELS WERE LODGED INSIDE THE PLANTER AREA. THE FRONT BUMPER, POSITION LIGHTS AND UNDERCARRIAGE WERE SERIOUSLY DAMAGED. AAA ROAD ASSISTANCE HAD TO BE CALLED TO PULL THE CAR OUT OF THE PLANTER. THE INCIDENT IS EXTREMELY SIMILAR TO OTHER SUCH INCIDENTS OF SUDDEN UNWANTED ACCELERATION DOCUMENTED IN YOUTUBE VIDEOS. WE HAVE OPENED A CLAIM WITH HYUNDAI, CASE # 962 9876.