2025 Hyundai Santa Fe Hybrid

The primary component failure is within the hybrid powertrain control architecture, specifically involving the transmission control system or internal transmission clutches/modules (TCM/HEV control module). The vehicle utilizes a 6-speed automatic transmission integrated with an electric motor. During highway cruising, the transmission locks into a single gear ratio or a protective "limp mode," resulting in a total loss of normal acceleration despite high engine RPMs. The vehicle and its components are fully intact and available for inspection upon request. My safety and the safety of others were put at severe risk because the sudden, unexpected loss of acceleration occurred while traveling at highway speeds in active traffic. When the transmission locked and power cut out, the vehicle rapidly shed speed and dropped to a hazardous 20-35 mph on a high-speed roadway. This created an immediate, extreme risk of a high-speed rear-end collision from vehicles traveling behind me, forcing me to make defensive lane changes toward the shoulder without normal engine power to navigate safely. This happens without warning no notices or errors pop up when it happens. The issue is intermittent and has been presented to an authorized Hyundai dealership technician multiple times. Because the vehicle often resets its communication modules and temporary limp-mode parameters once the ignition cycle is turned completely off and back on, the dealership technicians have encountered difficulty pulling permanent historical diagnostic trouble codes (DTCs). However, the failure patterns match a widely documented, repeating issue among 2025 Santa Fe Hybrid owners regarding HEV torque calculation or loose engine wiring harness pin tension

NHTSA ID

11766539

Incident

Sep 23, 2026

While driving on a highway at approximately 60 MPH, the vehicle abruptly suffered a catastrophic loss of power and entered "Limp Mode," creating a severe safety hazard on the roadway. The vehicle was safely maneuvered and pulled over to the side of the road. Upon shutting the vehicle down and attempting to restart it after a few minutes, the powertrain completely failed to engage, refusing to shift into either Drive or Reverse. The vehicle became entirely disabled and required a flatbed tow to the dealership. ​Dashboard Warning Messages: - ​"Transmission Control System" - ​"Check Hybrid System" ​Diagnostic Trouble Codes (DTCs): - ​P177700 (Transmission / Hybrid Powertrain Control Malfunction) - ​P178400 (Transmission Control System / Electric Oil Pump or Actuator Circuit Fault)

NHTSA ID

11765583

Incident

Sep 2, 2026

**What component or system failed, and is it available for inspection?** The vehicle's electrical/power system failed, causing a complete loss of power while driving. This is the fourth occurrence of this failure. The vehicle is currently at the Hyundai dealership and available for inspection. **How was your safety or the safety of others put at risk?** The power failure occurred while driving on a busy road. The driver struggled to safely maneuver the vehicle (executing a U-turn) to get out of traffic and reach a safe location. The vehicle had to be towed as a result. **Has the problem been reproduced or confirmed by a dealer or independent service center?** The vehicle has been brought to the Hyundai dealership for this same issue four times. As of the most recent update, the dealership has not been able to identify the root cause or confirm a fix. **Has the vehicle or component been inspected by the manufacturer, police, insurance representatives, or others?** The vehicle is currently with the Hyundai dealership (manufacturer-affiliated) for the fourth time for inspection related to this issue. No inspection by police or insurance has been reported. **Were there any warning lamps, messages, or other symptoms prior to the failure, and when did they first appear?** There were no warning lamps, messages, or other symptoms prior to the failure. Warning lamps/messages appeared only after the vehicle lost power.

NHTSA ID

11764110

Incident

Jun 9, 2026

The car suddenly loses acceleration; the engine still runs and revs to ~3,000 RPM. The car can't drive over 35mph; no check engine light at all. The dealer said a high-pressure fuel pump caused it and replaced it under warranty; after 3 days, the same problem happened again. This is extremely dangerous if the vehicle is on a highway and suddenly loses acceleration. This could be fatal for the driver and other vehicles around it.

NHTSA ID

11763033

Incident

Aug 27, 2026

First Incident – XXX Weekend ([XXX]) Accelerating at an on-ramp to a major highway (I-37S) in [XXX], vehicle suddenly lost power. Speed dropped from 60 mph to 45 mph, then 28 mph, in a 65 mph zone during rush hour traffic. No apparent cause: had ¾ tank of fuel, a clean maintenance history, and no prior issues. Managed to reach the shoulder and, after several minutes, able to exit the highway. Vehicle would not accelerate above 35–45 mph and stayed around 30mph, and the hybrid battery showed less than 25% charge. Notified Red McCombs Hyundai (original seller). When a loaner vehicle became available, we brought the Santa Fe in. After a week, the dealership stated they could not duplicate the problem and returned the vehicle to us. Second Incident – XXX ([XXX]) On a planned trip from [XXX] to [XXX], again experienced a sudden and severe loss of power. While merging onto I‑10W, in [XXX], the vehicle speed dropped from 80 mph to 60, then 50, then 38 mph. Able to avoid a collision because of an unusually wide median where I could safely stop. Used GPS to find a local Hyundai dealer - Casa Hyundai of [XXX] - and drove there, using surface roads only. Turned vehicle in for maintenance and continued trip using a loaner vehicle. Casa Hyundai reported, days later, that despite logged error messages indicating problem with hybrid system and advising user to immediately stop, they were unable to isolate problem. Third Incident – XXX (Unknown location in [XXX]) Entering I-10E after fuel stop (80mph zone) and accelerating hard on a slight incline, again experienced sudden loss of power, slowing to less than 40 mph. Drove on shoulder for two miles to next exit 284 and stopped w/motor running to recharge. No error codes or warnings displayed on dash. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11762194

Incident

Jul 4, 2026

The contact owns a 2025 Hyundai Santa Fe. The contact stated that while driving 40 MPH, the instrument panel went blank. The contact was able to pull over safely after the failure. The contact associated the failure with NHTSA Campaign Number: 26V047000 (Electrical System); however, the VIN was not include in the recall. The dealer was contacted by phone. The manufacturer was contacted by phone and made aware of the failure. The failure mileage was approximately 7,900.

NHTSA ID

11761919

Incident

Aug 10, 2026

Mileage

7,900 mi

While driving, the vehicle suddenly lost motive power on the highway and would not accelerate beyond approximately 20 mph despite accelerator input. There were no warning lights or check-engine light. The condition created a safety hazard because the vehicle could not maintain normal traffic speed. Hyundai dealer has been unable to determine the cause on other vehicles with the same problem, and was trying to discourage me from reporting this. They also said that they'd keep the car for 3 days, and likely return it with no diagnosis, so do I really want to go through this? They seemed unconcerned that this is a very dangerous issue in a highway.

NHTSA ID

11761734

Incident

Sep 2, 2026

I've had this vehicle for 13 months, and it has roughly 13K miles on it. Since 7/3/26, it has been in the service department at Hyundai of Noblesville on three separate occasions. This all started on 7/3/26 when we were driving on the interstate and out of nowhere the vehicle lost critical power and would not go more than 20 MPH. There was some kind of warning message that momentarily popped up but then disappeared. We were so rattled, we didn't get a chance to take notice of what it said. It was towed to the dealership and they said they cleared the codes and drove it a little and the problem was resolved. It was driving OK and then on 7/15/26, we had just got onto the interstate and there was a sudden loss of power AGAIN. We had it towed to the dealership. They replaced the high pressure fuel pump and assured us that the problem was resolved. Then on 8/29/26, the same thing happened again on the interstate--critical loss of power. Had it towed to the dealership again. This morning, they say that it is the fuel pump railings that are the issue. I have placed a formal Hyundai Corporate Case and I am notifying you of this safety issue which presents major risk to the safety of anyone in the car.

NHTSA ID

11760870

Incident

Aug 29, 2026

Some Santa Fe Hybrid (MX5A HEV) vehicles may have walk-in switches that are not fully secured. This bulletin provides instructions to trim the seat cover and replace the walk-in switch with improved parts.

Some Santa Fe (MX5A) and Santa Fe Hybrid (MX5A HEV) vehicles may exhibit a 12-volt battery drain due to the passive entry feature of the Digital Key 2 premium causing repeated wakeup of the vehicle. This bulletin provides instructions to perform software updates for the Ultra-Wide Band (UWB) and Body Domain Control (BDC) modules.

Some Santa Fe (MX5A) and Santa Fe Hybrid (MX5A HEV) vehicles equipped with natural leather or Nappa leather seating surfaces may exhibit wrinkling on the first or second row seat cushions or seat backs, or tearing along the perforation holes due to the stiffness of the leather material. This bulletin provides instructions to replace the wrinkled or torn seat covers.

Some Santa Fe (MX5A) and Santa Fe Hybrid (MX5A HEV) vehicles equipped with power seats with or without Integrated Memory System (IMS) may produce buzz, squeak, rattle noises when the driver’s front seat is adjusted forward or backwards due to friction within the motor’s tube. This bulletin provides instructions to remove the motor tube.

This bulletin provides information related to the navigation and head unit software changes introduced in the 2026 1st Navigation Map and Software Update. The changes may vary depending on vehicle type, model, and navigation system. Refer to the 2026 1st Navigation Map and Software Update Key Improvements and Additional Improvements tables in this TSB for a list of specific changes. The software can be downloaded via Navigation Updater (NAU) and updated by USB.

The National Highway Traffic Safety Administration (NHTSA) has issued an urgent safety advisory regarding dangerous, counterfeit driver‑side airbag inflators manufactured by Jilin Province Detiannuo Automobile Safety System Co., Ltd. (DTN), that have been identified in U.S. vehicles following prior crashes, theft, or non‑certified airbag replacements. These inflators are not approved for use, may rupture during deployment, and have caused serious injuries and fatalities. Please see attached announcement, provided by NHTSA, for more details.