NHTSA owner reports · September 18, 2026 snapshot.
Engine And Engine Cooling complaints
31 reportsClear category filter84,850 miles · Dec 23, 2024
Engine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated that while driving at various speeds, the engine stalled. The engine would decrease in engine RPMs. The vehicle was able to restart however the failure recurred. The vehicle was towed to the residence, and then to a dealer. The vehicle was diagnosed and the contact was provi…
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The contact owns a 2015 Kia Optima. The contact stated that while driving at various speeds, the engine stalled. The engine would decrease in engine RPMs. The vehicle was able to restart however the failure recurred. The vehicle was towed to the residence, and then to a dealer. The vehicle was diagnosed and the contact was provided manufacturer's recall number: PI1802A. The manufacturer was contacted and informed the caller the ECU Logic Upgrade should have been completed first before the engine could be repaired. The failure was recurring and the contact parked the vehicle to be not driven no longer as it was a safety concern. The failure mileage was 84,850.
NHTSA ODI #11632148
92,394 miles · Aug 20, 2024
Electrical SystemEngine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. Additionally, the check engine warning light illuminated, and the vehicle turned off unintendedly. The vehicle was towed to the dealer where it …
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The contact owns a 2015 Kia Optima. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. Additionally, the check engine warning light illuminated, and the vehicle turned off unintendedly. The vehicle was towed to the dealer where it was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure; however, the contact was informed that the repair was not covered under the Technical Service Bulletin NHTSA ID: 10252085 (Electrical System, Engine and Engine Cooling); with a similar failure description. The failure mileage was approximately 92,394.
NHTSA ODI #11609618
84,000 miles · Jun 11, 2024
EngineEngine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH and depressing the accelerator pedal to merge onto the highway, the vehicle failed to respond as needed. The contact stated that she had not observed any warning lights being illuminated. The contact pulled off the highway and had the vehic…
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The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH and depressing the accelerator pedal to merge onto the highway, the vehicle failed to respond as needed. The contact stated that she had not observed any warning lights being illuminated. The contact pulled off the highway and had the vehicle towed to a local mechanic. The mechanic diagnosed the vehicle and determined that the engine had no oil and had seized. The mechanic determined that the engine needed to be replaced. The vehicle was repaired. The manufacturer was not informed of the failure. The failure mileage was approximately 84,000.
NHTSA ODI #11593662
73,000 miles · May 16, 2024
Engine And Engine CoolingCrash
The contact owns a 2015 Kia Optima. The contact stated while the daughter was driving at approximately 80 MPH and attempting to pass a tractor-trailer in the left lane, the vehicle behind her aggressively merged into the same lane causing a crash to the passenger side of the vehicle. The other vehicle fled the scene. The contact…
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The contact owns a 2015 Kia Optima. The contact stated while the daughter was driving at approximately 80 MPH and attempting to pass a tractor-trailer in the left lane, the vehicle behind her aggressively merged into the same lane causing a crash to the passenger side of the vehicle. The other vehicle fled the scene. The contact's daughter merged to the shoulder of the road. There was damage to the front passenger side door, and front passenger wheel well, and tire. The vehicle failed to restart. The police were on the scene however no Police Report was filed. There were no injuries reported. The vehicle was towed to a collision center for cosmetic repairs but the vehicle failed to start. The vehicle was then towed to a local dealer. The dealer diagnosed that the engine had failed and needed to be replaced. The dealer mentioned a recall related to the engine, but it was not eligible for engine replacement because the vehicle had not had a software update performed for the engine. The vehicle was not repaired. The contact had researched online and related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The manufacturer was notified of the failure. The failure mileage was approximately 73,000.
NHTSA ODI #11589024
Mileage unknown · Apr 24, 2024
EngineEngine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated that while driving 30 MPH, there was an abnormal smoke odor inside the interior of the vehicle. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who determined that there was an oil leak in the engine compartment. The vehicle was not repa…
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The contact owns a 2015 Kia Optima. The contact stated that while driving 30 MPH, there was an abnormal smoke odor inside the interior of the vehicle. No warning lights were illuminated. The vehicle was taken to an independent mechanic, who determined that there was an oil leak in the engine compartment. The vehicle was not repaired. The vehicle was then taken to the dealer, who diagnosed a failure with the engine, determining that the engine was consuming oil abnormally quick, and the engine might soon need to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was unknown.
NHTSA ODI #11584987
151,000 miles · Apr 2, 2024
Engine And Engine CoolingService Brakes, Hydraulic
The contact owns a 2015 Kia Optima. The contact received notification of NHTSA Campaign Number: 23V652000 (Service Brakes, Hydraulic) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made …
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The contact owns a 2015 Kia Optima. The contact received notification of NHTSA Campaign Number: 23V652000 (Service Brakes, Hydraulic) however, the part to do the recall repair was not yet available. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact stated that when starting the vehicle, the check engine and several other warning lights illuminated. The contact stated that the vehicle was overheating, and the contact was concerned about a possible fire. The contact had driven the vehicle to an independent mechanic who was unable to duplicate the failure. Additionally, the contact stated that while driving at approximately 60 MPH, the vehicle independently accelerated. The contact stated that several unknown warning lights were illuminated. The contact pulled over and stopped the vehicle. The contact stated that she waited about 30 minutes and restarted the vehicle and drove back to her residence. The manufacturer was not made aware. The failure mileage was approximately 151,000. VIN tool confirms parts not available.
NHTSA ODI #11580595
81,000 miles · Dec 22, 2023
Engine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated while driving 20 MPH, the vehicle inadvertently lost motive power. The contact pulled over to the shoulder of the roadway, where the vehicle failed to restart. The check engine and low engine oil warning lights were illuminated. The vehicle was towed to an independent mechan…
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The contact owns a 2015 Kia Optima. The contact stated while driving 20 MPH, the vehicle inadvertently lost motive power. The contact pulled over to the shoulder of the roadway, where the vehicle failed to restart. The check engine and low engine oil warning lights were illuminated. The vehicle was towed to an independent mechanic, who determined that an unknown fluid had leak and damaged the electrical components in the engine compartment, causing the engine to seize. The vehicle was not repaired. The manufacturer was notified of the failure but referred the contact to the NHTSA hotline for assistance. The approximate failure mileage was 81,000.
NHTSA ODI #11561537
102,589 miles · Dec 6, 2023
EngineEngine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated that while driving at approximately 40 MPH, the engine seized. After restarting the vehicle, the vehicle shut off. The vehicle was towed to the local dealer, where it was diagnosed that the engine had seized and needed to be replaced. The contact was informed that there was …
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The contact owns a 2015 Kia Optima. The contact stated that while driving at approximately 40 MPH, the engine seized. After restarting the vehicle, the vehicle shut off. The vehicle was towed to the local dealer, where it was diagnosed that the engine had seized and needed to be replaced. The contact was informed that there was metal in the intake and exhaust cam shaft. There were metal shavings in the oil. The contact was also informed that the pistons were off by twenty-four degrees. There was an indication that cylinders #1, #2, and #4 had misfired. The vehicle was not repaired. The manufacturer was contacted, but no assistance was provided. The failure mileage was approximately 102,589.
NHTSA ODI #11558789
184,000 miles · Jun 13, 2023
Engine And Engine CoolingFire
The contact owns a 2015 Kia Optima. The contact's daughter was driving at approximately 60 MPH when numerous lights on the dashboard illuminated. The contact stated that her daughter said that the vehicle stalled, however, she was in the right-hand lane and pulled over. The daughter said that smoke was being emitted from the eng…
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The contact owns a 2015 Kia Optima. The contact's daughter was driving at approximately 60 MPH when numerous lights on the dashboard illuminated. The contact stated that her daughter said that the vehicle stalled, however, she was in the right-hand lane and pulled over. The daughter said that smoke was being emitted from the engine compartment. The contact stated her daughter was picked up by family and the vehicle was left at the side of the highway. The contact stated that the daughter's companion retrieved the vehicle. The contact stated that he opened the hood and checked the oil and observed that there was no oil showing on the dipstick. The contact filled the vehicle's oil reservoir and started the vehicle. The contact said that he also reported that all panel warnings illuminated and the vehicle had begun to emit smoke. The contact stated he pulled off the roadway, opened the hood, and observed smoke and flames being emitted from under the engine block. The contact stated he had immediately closed the hood and moved away from the vehicle. The contact stated that he reported that the vehicle continued to emit smoke but no more flames were observed. The contact had the vehicle towed to a local dealer, where it was diagnosed and determined that the engine had seized and needed to be replaced. The vehicle had not been repaired. The manufacturer had been informed of the failure. The failure mileage was approximately 184,000.
NHTSA ODI #11526832
83,000 miles · Apr 3, 2023
Engine And Engine Cooling
The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH, the contact stated he heard an abnormal knocking sound coming from the engine compartment. The contact observed white smoke coming from under the hood. The contact was able to pull over with the engine still running however, when he stoppe…
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The contact owns a 2015 Kia Optima. The contact stated while driving approximately 40 MPH, the contact stated he heard an abnormal knocking sound coming from the engine compartment. The contact observed white smoke coming from under the hood. The contact was able to pull over with the engine still running however, when he stopped and turned off the vehicle, he was unable to restart the vehicle. The contact stated that the oil and battery warning lights were illuminated. The contact had the vehicle towed to an independent mechanic where it was diagnosed and determined that the engine needed to be replaced. The vehicle had not been repaired. The manufacturer had not been informed of the failure. The contact researched online and related the failure to NHTSA Campaign Number: 17V224000 (Engine and Engine Cooling). The failure mileage was approximately 83,000.
NHTSA ODI #11515219
Official recalls
4Sep 25, 2023
Kia America, Inc. (Kia) is recalling certain 2010-2019 Borrego, 2014-2016 Cadenza, 2010-2013 Forte, Forte Koup, Sportage, 2015-2018 K900, 2011-2015 Optima, 2011-2013 Optima Hybrid, Soul, 2012-2017 Rio, 2011-2014 Sorento, and 2010-2011 Rondo vehicles. The Hydraulic Electronic Control Unit (HECU) may experience 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 HECU fuse, free of charge. Interim notification letters, notifying owners of the safety risk, were mailed November 14, 2023. Owner notification letters were mailed March 29, 2024 through June 18, 2024. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC284.
May 10, 2021
Kia Motors America (Kia) is recalling certain 2013-2015 Optima and 2014-2015 Sorento vehicles previously recalled under recall 20V-519. Brake fluid may leak inside the Hydraulic Electronic Control Unit (HECU), possibly resulting in an electrical short.
Consequence & remedy
Consequence: An electrical short in the HECU increases the risk of a fire while parked or driving.
Remedy: Owners are advised to park outside and away from other vehicles and structures until the recall repair is completed. Dealers will install a new multi-fuse, and inspect the HECU for leaks, replacing the HECU if necessary, free of charge. Owner notification letters were mailed on July 2, 2021. This recall supersedes previous NHTSA recall number 20V-519. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC212.
Aug 27, 2020
Kia Motors America (Kia) is recalling certain 2013-2015 Optima and 2014-2015 Sorento vehicles. Brake fluid may leak inside the Hydraulic Electronic Control Unit (HECU), possibly resulting in an electrical short.
Consequence & remedy
Consequence: If the HECU short circuits, there is an increased risk of an engine compartment fire.
Remedy: Kia will notify owners, and dealers will inspect the HECU for leaking brake fluid and replace the HECU if necessary, free of charge. Owners are advised to park outside and away from other vehicles and structures until the recall repair is completed. The recall began October 20, 2020. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC197.
Dec 19, 2018
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence & remedy
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
Additional source detail variants (2)
Engine
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
Fuel System, Gasoline:delivery:hoses, Lines/piping, And Fittings
Kia Motors America (Kia) is recalling certain 2011-2017 Optima, 2012-2017 Sorento and 2011-2018 Sportage vehicles that previously received an engine replacement under recall number 17V-224, warranty, or the Knock Sensor Detection System (KSDS) Product Improvement Campaign. The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak.
Consequence: A fuel leak in the presence of an ignition source can increase the risk of a fire.
Remedy: Kia has notified owners, and dealers will inspect and replace the fuel pipe, as necessary, free of charge. The recall began January 17, 2019. Owners may contact Kia customer service at 1-800-333-4542. Kia's number for this recall is SC172.
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
4AQ23002 · 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.
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.
DP21003 · Throttle Control System Vulnerabilities
Opened Nov 12, 2021 · Closed Jun 20, 2023
Status: closed (inferred from source dates) · Vehicle Speed Control:throttle
The Office of Defects Investigation (ODI) of the National Highway Traffic Safety Administration (NHTSA) received a petition letter dated October 10, 2021, requesting an investigation of possible defects in the electronic throttle control (ETC) system on certain Kia vehicles resulting in the opening of DP21-003. Accordingly, Model Year (MY) 2005-2016 Kia Optima/K5, MY 2006-2015 Kia Sorento, MY 2007-2016 Hyundai Elantra, MY 2007-2016 Hyundai Santa Fe, MY 2006-2015 Hyundai Sonatas are all part of the subject population. The petition was originally filed as a Vehicle Owner Questionnaire that can be reviewed at NHTSA.gov under reference (ODI) number 11439675.On November 12, 2021, ODI opened Defect Petition DP21-003 to evaluate the petitioner?s request. ODI performed trend analyses of the VOQs related to vehicle speed control issues for all the subject vehicles and found that none of the 52 Model/Model Year Hyundai/Kia vehicles demonstrated any actionable trend that warranted an investigation.Petitioners submitted 1119 VOQs and non-VOQ cases in which sudden uncommanded acceleration (SUA) or loss of motive power (LOMP) incidents were alleged.For the 1119 reports, 220 were incidents involving crashes, from which 69 subject Hyundai-Kia vehicles were inspected by Hyundai/Kia dealer technicians, Hyundai/Kia engineers, and/or third-party representatives.ODI found the inspections identified no vehicle defects related to the ETC system.Of the 220 crash-involved reports, 13 Event Data Recorder (EDR) records were downloaded successfully and 11 of those indicated driver error: (i.e.) pedal misapplication.A condition where the accelerator pedal is mistakenly applied instead of the brake pedal when the driver wants to stop the vehicle.In addition, ODI reviewed a scientific journal paper published in Forensic Science International in 2016 by Mr. Park et al ., as well as related test videos. ODI does not believe there is any evidence of uncontrollable SUA occurrences in any of the tests reviewed. NHTSA's Office of Vehicle Safety Compliance (OVSC) reviewed the allegations regarding the potential noncompliance with Federal Motor Vehicle Safety Standard No. 124.Based on the information provided, the Agency concludes there is insufficient information for us to determine if a possible non-compliance exists.Finally, both Hyundai and Kia informed ODI that all their vehicles manufactured after 2012 were equipped with an ETC management system, in which the engine speed will go to idle when the system sees signals from both the brake pedal and accelerator pedal at the same time; this is commonly known as the brake-throttle override system.After thoroughly assessing the material submitted by the petitioner, information already in NHTSA's possession, information submitted by Hyundai and Kia in response to an Information Request letter, and the potential risks to safety implicated by the petitioner's allegation, NHTSA does not believe that a formal investigation is warranted. After full consideration of appropriate factors, the petition is denied. A Federal Register Notice (FRN) further detailing NHTSA?s reasons for denial of the petition will be published.
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.