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2015 Hyundai Sonata Hybrid

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2015 Hyundai Sonata Hybrid do not stand out strongly from the model-year median of 23.

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How this year compares

Owner complaints by model year

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Counts vary with age, sales and reporting. They are not failure rates.

What owners reported most

All reported categories

Tap a category to read its complaints. One report may name several components.

When problems were reported

Mileage at the reported incident

42 reports with mileage · 10 unknown

NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.

What to inspect

Issues worth paying extra attention to based on owner reports.

  • Electrical System. Review the 24 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine. Review the 17 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Service Brakes. Review the 8 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

4 crash reports3 fire reports3 injury reports

Power Train complaints

7 reports
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Mileage unknown · Apr 16, 2024
Power TrainService Brakes, Air

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. La…

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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.

NHTSA ODI #11583377

74,680 miles · Nov 27, 2023
Power Train

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 ill…

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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.

NHTSA ODI #11556952

Mileage unknown · Jul 3, 2019
Power TrainService BrakesVehicle Speed Control

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…

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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.

NHTSA ODI #11229352

30,000 miles · Jan 8, 2018
Electrical SystemPower TrainUnknown Or Other

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

NHTSA ODI #11061134

10,000 miles · May 31, 2017
Power TrainSeat BeltsCrashInjury

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…

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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.

NHTSA ODI #10992400

82,000 miles · Apr 21, 2017
Electrical SystemPower TrainVehicle Speed Control

ABOUT AN HOUR INTO DRIVING HOME ON THE FREEWAY, MY CAR ALERT SYSTEM WENT OFF AND THE CAR AUTOMATICALLY BEGAN TO DECELERATE AND THE DASHBOARD DISPLAY SHOWED INSTRUCTIONS TO CHECK HYBRID CHARGING SYSTEM AND TO CHECK SURROUNDINGS AND TO PULL OVER WHEN SAFE AND TO NOT DRIVE VEHICLE. THE CHECK ENGINE LIGHT, THE NEEDS MAINTENANCE LIG…

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ABOUT AN HOUR INTO DRIVING HOME ON THE FREEWAY, MY CAR ALERT SYSTEM WENT OFF AND THE CAR AUTOMATICALLY BEGAN TO DECELERATE AND THE DASHBOARD DISPLAY SHOWED INSTRUCTIONS TO CHECK HYBRID CHARGING SYSTEM AND TO CHECK SURROUNDINGS AND TO PULL OVER WHEN SAFE AND TO NOT DRIVE VEHICLE. THE CHECK ENGINE LIGHT, THE NEEDS MAINTENANCE LIGHT AND THE CHECK OIL LIGHT ALL CAME ON. AFTER ABOUT 15 SECS MY VEHICLE LOST ALL POWER BUT DID NOT TURN OFF; THE STEERING WHEEL BECAME LOCKED. I PLACED THE CAR INTO PARK AND RESTARTED IT AND THE WARNING ALERT ALARM CEASED, BUT NOW THE CHECK ENGINE LIGHT STAYED ON. THE STEERING WHEEL WAS MOVABLE AGAIN AND I WAS ABLE TO PULL TO THE SHOULDER WHERE A CALIFORNIA HIGHWAY PATROL OFFICER PULLED UP AND ASKED ME IF I WAS HAVING TROUBLE. AFTER OUR CONVERSATION, I WAS ABLE TO CONTINUE THE ADDITIONAL 40 MILE DRIVE HOME AS THE LOCAL HYUNDAI DEALERSHIPS WERE CLOSED UNTIL THE NEXT DAY, SATURDAY MARCH 18. I WAS ABLE TO DROP MY CAR OFF IN THE AFTERNOON BUT DUE TO THEIR BOOKED SCHEDULE, IT COULD NOT BE LOOKED AT UNTIL MONDAY MARCH 20TH AND STAYED OVER NIGHT. THE TECHNICIAN CALLED ME THAT DAY AND STATED THAT THE CAR TEST RAN ON IT CAME BACK PASSING AND NO ISSUES FOUND AND THAT THEY DROVE IT ABOUT 20 MILES AND NO ISSUES AND I WAS ABLE TO PICK UP MY CAR ON TUESDAY. HOWEVER, THE SAME SYSTEM ISSUE HAPPENED 3 MORE TIMES BEFORE I WAS ABLE TO TAKE IT BACK INTO THE DEALERAHIP LATER THAT WEEK AND IT HAS BEEN THERE AS OF 4/21/2017. I RECEIVED A CALL TODAY THAT A REPLACEMENT HYBRID BATTERY WAS INSTALLED AND AFTER MORE TESTS I MAY GET MY CAR BACK.

NHTSA ODI #10979806

5,000 miles · Dec 5, 2015
Electrical SystemEnginePower Train

WHEN PRESSING THE ACCELERATE PEDAL THERE SEEMS TO BE A DELAY IN RESPONSE. THE DELAY CAN BE AS SHORT AS A FEW MILLISECONDS TO ALMOST 3 ENTIRE SECONDS. THIS PROBLEM HAPPENS RANDOMLY, AND MAKES MY WIFE AND I VERY NERVOUS WHEN TRYING TO MANEUVER OR PROCEED INTO TRAFFIC AFTER BEING STOPPED.

NHTSA ODI #10808593

Official recalls

4

23V651000 · Service Brakes, Hydraulic:antilock/traction Control/electronic Limited Slip:control Unit/module

Sep 22, 2023

Hyundai Motor America (Hyundai) is recalling certain 2011-2015 Elantra, Genesis Coupe, Sonata Hybrid, 2012-2015 Accent, Azera, Veloster, 2013-2015 Elantra Coupe, Santa Fe, 2014-2015 Equus, 2010-2012 Veracruz, 2010-2013 Tucson, 2015 Tucson Fuel Cell, and 2013 Santa Fe Sport vehicles. The Anti-Lock Brake System (ABS) module may leak brake fluid internally and cause an electrical short, which can result in an engine compartment fire while parked or driving.

Consequence & remedy

Consequence: An engine compartment fire while parked or driving can increase the risk of injury.

Remedy: Owners are advised to park outside and away from structures until the recall repair is complete. Dealers will replace the ABS fuse, free of charge. Owner notification letters were mailed April 10, 2024 through October 11, 2024. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 251.

17V617000 · Seat Belts:front:anchorage; Seat Belts:pretensioner

Oct 4, 2017

Hyundai Motor America (Hyundai) is recalling certain 2011-2014 Sonata and 2011-2015 Sonata Hybrid vehicles previously repaired under recall campaign 17V-152. The seat belt linkages for both front seat belts may detach from the seat belt anchor pretensioners.

Consequence & remedy

Consequence: If the seat belt linkage detaches from the seat belt anchorage, it can not properly restrain the occupant in the event of a crash, increasing the risk of injury.

Remedy: Hyundai will notify owners, and dealers will again verify the connection between the seat belt linkage and the pretensioner and additionally install a warning label to prevent future seat belt linkage detachment, free of charge. The recall began November 6, 2017. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 169.

Additional source detail variants (2)

Seat Belts:pretensioner

Hyundai Motor America (Hyundai) is recalling certain 2011-2014 Sonata and 2011-2015 Sonata Hybrid vehicles previously repaired under recall campaign 17V-152. The seat belt linkages for both front seat belts may detach from the seat belt anchor pretensioners.

Consequence: If the seat belt linkage detaches from the seat belt anchorage, it can not properly restrain the occupant in the event of a crash, increasing the risk of injury.

Remedy: Hyundai will notify owners, and dealers will again verify the connection between the seat belt linkage and the pretensioner and additionally install a warning label to prevent future seat belt linkage detachment, free of charge. The recall began November 6, 2017. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 169.

Seat Belts:front:anchorage

Hyundai Motor America (Hyundai) is recalling certain 2011-2014 Sonata and 2011-2015 Sonata Hybrid vehicles previously repaired under recall campaign 17V-152. The seat belt linkages for both front seat belts may detach from the seat belt anchor pretensioners.

Consequence: If the seat belt linkage detaches from the seat belt anchorage, it can not properly restrain the occupant in the event of a crash, increasing the risk of injury.

Remedy: Hyundai will notify owners, and dealers will again verify the connection between the seat belt linkage and the pretensioner and additionally install a warning label to prevent future seat belt linkage detachment, free of charge. The recall began November 6, 2017. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 169.

17V152000 · Seat Belts:front:anchorage

Mar 8, 2017

Hyundai Motor America (Hyundai) is recalling certain 2011-2014 Sonata and 2011-2015 Sonata Hybrid vehicles. In the affected vehicles, the seat belt linkages for both front seat belts may detach from the seat belt anchor pretensioners.

Consequence & remedy

Consequence: In the event of a crash, if the seat belts detach from the anchor pretensioners, it can increase the risk of injury.

Remedy: Hyundai will notify owners and dealers will inspect the connection between the seat belt linkages and the seat belt anchor pretensioners, repairing them as necessary, free of charge. The recall is expected to begin April 7, 2017. Owner's may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for the recall is 160.

16V726000 · Visibility:sun/moon Roof Assembly

Oct 11, 2016

Hyundai Motor America (Hyundai) is recalling certain model year 2015-2016 Sonata Hybrid vehicles manufactured December 8, 2014, to August 18, 2015, and Hyundai Sonata vehicles manufactured May 28, 2014, to March 18, 2016, equipped with the panoramic sunroof option. Due to a bonding issue with the sunroof wind deflector, the sunroof panel on the affected vehicles may detach while driving.

Consequence & remedy

Consequence: If the sunroof detaches from the vehicle it could become a road hazard, increasing the risk of a crash.

Remedy: Hyundai will notify owners, and dealers will repair the wind deflector anchor plate, free of charge. The recall began December 2016. Owners may contact Hyundai customer service at 1-800-633-5151. Hyundai's number for this recall is 152.

Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗

NHTSA investigations

4

AQ23002 · Hyundai And Kia Abs Module Fires

Opened Nov 17, 2023 · No close date supplied

Status: open (inferred from source dates) · Service Brakes, Hydraulic:antilock/traction Control/electronic Limited Slip:control Unit/module

The Office of Defects Investigation (ODI) has received eight Hyundai Motor America (Hyundai) and eight Kia America, Inc. (Kia) Part 573 Recall Reports between 2016 and 2023. The combined 16 safety recalls all involve the antilock braking system (ABS) modules or Hydraulic Electronic Control Units (HECU) manufactured by the equipment supplier Mando. The Part 573 Recall Reports contain varying defect descriptions and differing remedy descriptions for the same or similar equipment supplied by Mando. Safety recalls included in this Audit Query (AQ) review include: Hyundai recalls 20V-520, 20V-543, 21V-161, 21V-160, 21V-303, 22V-056, 22V-810, and 23V-651. Kia recalls 16V-815, 20V-518, 20V-519, 21V-137, 21V-331, 22V-051, 22V-800, and 23V-652 The purpose of this AQ is to evaluate the timeliness and scoping of Hyundai and Kia’s defect decision making and adherence with reporting requirements; and understand the varying defect descriptions and remedies between these recalls.

DP22005 · Pedestrian Alert Sounds

Opened Jan 27, 2023 · Closed Aug 7, 2023

Status: closed (inferred from source dates) · Electrical System:propulsion System

NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, NHTSA opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified NHTSA he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by NHTSA regarding the subject matter of the petition.

DP22003 · Loss Of Motive Power

Opened Sep 12, 2022 · Closed Dec 12, 2023

Status: closed (inferred from source dates) · Engine

The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021. The Petitioners cited examples of complaints indicating that the subject vehicles were experiencing rapid loss of engine oil due to oil drain plug back outs, resulting in loss of motive power and/or catastrophic engine damage. Additional complaints were provided which alleged that the oil drain pans lack sufficient structural integrity and are susceptible to cracking. The petition itself can be reviewed at NHTSA.gov under ODI number 11481745. On September 12, 2022, the Office of Defects Investigation (ODI) opened Defect Petition (DP22-003) to evaluate the Petitioners’ request. The Petitioners have provided additional complaints within four supplemental letters dated January 31, 2023, March 21, 2023, May 23, 2023, and August 4, 2023. ODI’s evaluation included the review and analysis of the complaints and supporting information submitted by the Petitioners, as well as additional complaints submitted directly to NHTSA which referenced either the oil drain plug or a crack in the oil pan. After reviewing the available data, ODI has not identified evidence that would support opening a defect investigation into the oil drain pan assemblies of the subject vehicles. Based on a review of the available information, a loss of motive power resulting from an oil drain plug back out has not occurred between the initial sale of a vehicle and the completion of its first oil change. If during an oil change service, a technician fails to remove the existing drain plug gasket before installing a new gasket, it is likely that a proper seal between the drain plug and the oil pan will not be made. An improper seal between the drain plug and oil pan could lead to the backing out on the drain plug, resulting in the sudden loss of oil while driving. Additionally, the provided examples of oil pan cracks were localized to the immediate vicinity of the oil drain plug and/or appeared to be the result of direct-contact with a tool during servicing.  There is no information to support that a vehicle-based defect exists relating to the oil pan assembly, and instead the documented incidents are related to the failure to follow the proper maintenance procedures during oil change service. In October 2023, Hyundai published a Technical Service Bulletin (TSB) that provided detailed instructions for oil change service on its gasoline powered vehicles, specifically highlighting the need to remove and replace the existing drain plug gasket prior to reinstalling the drain plug. After a thorough review of the material submitted by the petitioner, the information already in NHTSA's possession, and the potential risks to motor vehicle safety implicated by the petitioners' allegations, NHTSA does not believe that a formal investigation is warranted. Therefore, the petition is denied. A Federal Register Notice (FRN) further detailing NHTSA’s reasons for denial of the petition will be published. The reference numbers for the complaints to NHTSA cited by the petitioner can be found in the petition submission documents in the public file for DP22-003. To review those complaints and the additional complaints ODI added to its evaluation which are cited in the Closing Resume ODI Report Identification Number document, go to NHTSA.gov.

EA19001 · Electrical Overstress

Opened Apr 19, 2019 · Closed Sep 19, 2024

Status: closed (inferred from source dates) · Air Bags: Air Bag/restraint Control Module

The Office of Defects Investigation (ODI) opened this investigation to determine if the failure of airbags to deploy during severe crashes, in certain vehicles, was the result of a safety related defect.  During the investigation a complex failure was studied that can result in non-deployment of subject vehicle air bags and other restraint system devices in severe crash events. The subject vehicles may be equipped with an airbag control unit (ACU) for the supplemental restraint system (SRS) Electronic Control Unit (ECU) manufactured by ZF-TRW.  The ECU receives signals from crash sensors mounted in the vehicle and deploys the vehicle air bags and seat belt pretensioners in accordance with manufacturer design specifications.  The ECU in the subject vehicles contains a model DS84 application-specific integrated circuit (ASIC) which controls the communication of the crash sensor signal, firing commands (i.e., when to deploy the airbag(s) and/or pretensioners), and fault information (e.g., diagnostic trouble codes). In September 2016, FCA announced recall 16V-668 for certain model year (MY) 2010 to 2014 Chrysler, Dodge and Jeep products manufactured with the subject ZF-TRW ACU.  In this recall, FCA discussed an EOS condition that resulted in a failure of the subject DS84 ASIC, which caused air bag non-deployment.  FCA noted that the defect condition had only been observed in vehicles equipped with sensor harnessing routed across the front of the vehicle.  Other FCA vehicles that also used the subject ACU, but were not equipped with cross-car harnessing, had not experienced EOS failures, despite similar time in service. During the course of this investigation, ODI sent two separate Information Request (IR) letters to six vehicle manufactures (including FCA, Hyundai, Honda, Kia, Mitsubishi, and Toyota) and one IR letter to ZF-TRW.  These IR letters resulted in ODI receiving comprehensive data from these manufacturers and suppliers. Studies of this data found that the DS84 ASIC does not have sufficient protection against negative electrical transients or electrical overstress (“EOS”) that can be generated in certain severe crashes.  An electrical transient occurs when the electrical power supplied to a circuit changes momentarily over a short duration of time.   In these severe crash cases, the crash sensors and other powered wiring can be damaged and short circuited so as to create a negative electrical transient of sufficient intensity and duration (that are outside the vehicle manufacturer's specification) to damage the ASIC before the restraint device deployment signal is received by the SRS ECU.  This damaged signal can lead to incomplete or nondeployment of the air bags and/or pretensioners.  Airbag non-deployment and/or lack of pretensioner operation can increase the risk or severity of injury in a crash.A total of 8 fatalities and 14 injuries were associated with known EOS events. The common element in all investigated manufacturers vehicles is the SRS ECU containing a DS84 ASIC manufactured by ZF-TRW.  The risk associated with the ASIC is equally shared among all OEMS involved in the investigation.  The actual real-world risk can be mitigated by other factors which were assessed by ODI during this investigation. The first mitigating factor involves protections built into the ACU design which protect the DS84 ASIC from damage.  There are multiple strategies and levels of protection employed by different OEMs that provide effective EOS mitigation.  The two most common strategies at the ACU level are circuit protection diodes on the remote senor signal lines, and current limiting resistors that protect critical components. The second mitigating factor is found at the vehicle level and involves the location and routing of the wires leading from the crash sensors to the SRS ECU.  If the wires are well protected in a crash and are not routed with other power wires carrying large currents, the risk for an EOS event is significantly reduced or eliminated. These design specific factors combine to produce a spectrum of risk for the vehicles equipped with ACUs using the DS84 ASIC.  Given the many of years of field exposure, it is possible to divide the subject population into two groups; vehicles which have experienced EOS events, and vehicles which have not experienced EOS field events. Four of the six OEMs involved in this investigation have experienced EOS field events on at least one of their models equipped with a DS84 ASIC.  All vehicle models (including the Toyota models identified in the Failure Report Summary of the opening resume for this investigation) with field events have been recalled.  In an abundance of caution, ODI kept this investigation open five years to monitor field performance and did not identify any field events on vehicles not included in existing safety recalls. Given the spectrum of risk identified in this investigation and that all vehicles with a demonstrated unreasonable risk have been recalled, ODI is closing this investigation. ODI is closing this investigation with the following manufacturer safety recalls: 16V-668, 18E-043, 18V-137, 18V-363, and 20V-024.  With the recall actions taken by the subject vehicle and equipment manufacturers, this investigation is closed. The closing of this investigation does not constitute a finding by NHTSA that a safety-related defect does not exists on other model or model year vehicles outside of the recall scopes. The agency reserves the right to take further action if warranted by the circumstances.