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2016 Ford Mustang

Owner reports · Recalls · Investigations

More warning signs than most Mustang years

Owner complaints for the 2016 Ford Mustang are substantially higher than the model-year median of 81.

About this comparison →

When problems were reported

Mileage at the reported incident

204 reports with mileage · 171 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.

  • Engine. Review the 75 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 72 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Back Over Prevention. Review the 52 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

13 crash reports6 fire reports10 injury reports

Steering complaints

12 reports
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Mileage unknown · Feb 25, 2026
Steering

The steering wheel over time is very loose and in my case i need to be very careful with it because I feel I am losing control on my car while driving. You can feel the steering wheel moving up and down without little to know force also while driving. I don't even drive that fast since my way to work is always in a school zones.…

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The steering wheel over time is very loose and in my case i need to be very careful with it because I feel I am losing control on my car while driving. You can feel the steering wheel moving up and down without little to know force also while driving. I don't even drive that fast since my way to work is always in a school zones.

NHTSA ODI #11720522

Mileage unknown · Jul 20, 2025
Steering

The steering wheel has a very distinct wobble. It moves in every direction as if the locking bolt is loose.

NHTSA ODI #11674902

Mileage unknown · Apr 25, 2024
Steering

It started to squeak

NHTSA ODI #11585329

Mileage unknown · Jul 27, 2023
EnginePower TrainSteering

2016 Ford Mustang V6 This is EXTREMELY concerning as it's a SAFETY issue losing power features while the vehicle is in motion. While driving the car provides an error message with a wrench sign/icon stating the transmission is not in Park, then it proceeds to shut down the car leaving us without power steering. The car need sto…

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2016 Ford Mustang V6 This is EXTREMELY concerning as it's a SAFETY issue losing power features while the vehicle is in motion. While driving the car provides an error message with a wrench sign/icon stating the transmission is not in Park, then it proceeds to shut down the car leaving us without power steering. The car need stopped, move the transmission to Park, and start the engine. Doing this clears the warning and you are able to drive the car without any problem. The two incidents occurrences were about 1 or 2 months apart. Below link shows other people having the same issue [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI #11534722

65,000 miles · Aug 12, 2020
Steering

THE STEERING IN MY 2016 FORD MUSTANG ECO BOOST WOULD BIND AT THE 11 O'CLOCK POSITION AND WOULD TAKE MUCH FORCE TO RETURN TO THE 12 O'CLOCK POSITION.THIS HAPPENED WHILE DRIVING AND WHILE SITTING STILL. I RETURNED THE CAR TO FORD FOR SERVICE, WHO TOLD ME I HAVE A DEFECTIVE "STEERING GEAR" AND REPLACE THE STEERING GEAR FOR $3,000.0…

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THE STEERING IN MY 2016 FORD MUSTANG ECO BOOST WOULD BIND AT THE 11 O'CLOCK POSITION AND WOULD TAKE MUCH FORCE TO RETURN TO THE 12 O'CLOCK POSITION.THIS HAPPENED WHILE DRIVING AND WHILE SITTING STILL. I RETURNED THE CAR TO FORD FOR SERVICE, WHO TOLD ME I HAVE A DEFECTIVE "STEERING GEAR" AND REPLACE THE STEERING GEAR FOR $3,000.00.

NHTSA ODI #11348903

6,800 miles · May 14, 2019
Steering

VEHICLE ELECTRONIC POWER STEER FAILED WHILE CRUISING APPROXIMATELY 60MPH ON A STRAIGHT SECTION OF ROAD. POWER ASSIST DISABLED, VEHICLE STILL DRIVEABLE JUST NO POWER ASSIST. PROBLEM WILL CLEAR ITSELF IF VEHICLE IS SHUT OFF AND RESTARTED BUT RETURNS A SHORT TIME LATER

NHTSA ODI #11207531

1,500 miles · Mar 14, 2019
Electrical SystemEngineSteering

VEHICLE SHUT DOWN 2 TIMES, ONCE IN TRAFFIC, DID RESTART, SEEMINGLY BECAUSE OF LOW SYSTEM VOLTAGE CAUSED BY A PARASITIC DRAW ON THE BATTERY WHICH HAS BEEN PRESENT SINCE NEW. MULTIPLE DTC'S IN HISTORY WHICH I CAN SUPPLY, FORD OF COURSE KNOWS NOTHING, BUT I HAVE SEEN MANY COMPLAINTS ON WEB PAGES ABOUT S550 BATTERY DRAW.

NHTSA ODI #11186897

14,000 miles · Oct 18, 2018
Steering

I JUST BOUGHT A 2016 MUSTANG GT FROM A LOCAL DEALERSHIP. SINCE THEN I'VE HAD MY CAR IN THEIR SHOP 5 TIMES FOR A INTERMETINT EXTREME PULL TO LEFT. I HAVE MADE SEVERAL ATTEMPTS TO HAVE THIS TAKEN CARE OF NOW IT IS GETTING TO THE POINT WHERE I AM HAVING TO RESEARCH POSSIBLE ISSUES AND TELL THEIR MECHANICS. THIS IS THE 3RD CAR I'VE …

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I JUST BOUGHT A 2016 MUSTANG GT FROM A LOCAL DEALERSHIP. SINCE THEN I'VE HAD MY CAR IN THEIR SHOP 5 TIMES FOR A INTERMETINT EXTREME PULL TO LEFT. I HAVE MADE SEVERAL ATTEMPTS TO HAVE THIS TAKEN CARE OF NOW IT IS GETTING TO THE POINT WHERE I AM HAVING TO RESEARCH POSSIBLE ISSUES AND TELL THEIR MECHANICS. THIS IS THE 3RD CAR I'VE BEEN THROUGH IN 2 MONTHS WITH THIS SAME ISSUE A 2013 MUSTANG GT AND A 2015 MUSTANG GT NOW MY NEWEST 2016 GT AS THEY ARE GETTING TO THE POINT OF TIRED OF ME AND BASICALLY TELLING ME IT'S TIME TO DEAL WITH FORD AND FIGURE OUT THIS ISSUE AND REPORT BACK TO THEM. I'M REALLY STARTING G TO LOSE FAITH IN THESE VEHICLES

NHTSA ODI #11141325

9,000 miles · Aug 7, 2017
Steering

HAVE HAD ISSUES THAT THE CAR DRIFTS TO THE RIGHT ACROSS LANES UNDER ANY AMOUNTS OF ACCELERATION OR SPEEDS. ONE TIRE HAD GONE COMPLETELY WARN OVER THE COURSE OF SEVERAL MONTHS WHILE THE PROBLEM WAS MOST NOTICEABLE. AFTER NEW TIRES WERE PUT ON THE PROBLEM SWITCHED ITSELF TO STEERING TO THE LEFT INSTEAD. THE SUSPENSION AND STEERING…

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HAVE HAD ISSUES THAT THE CAR DRIFTS TO THE RIGHT ACROSS LANES UNDER ANY AMOUNTS OF ACCELERATION OR SPEEDS. ONE TIRE HAD GONE COMPLETELY WARN OVER THE COURSE OF SEVERAL MONTHS WHILE THE PROBLEM WAS MOST NOTICEABLE. AFTER NEW TIRES WERE PUT ON THE PROBLEM SWITCHED ITSELF TO STEERING TO THE LEFT INSTEAD. THE SUSPENSION AND STEERING COMPONENTS WERE INSPECTED AS WELL AS TIRE ALIGNMENT. NO MECHANICAL ISSUES HAVE BEEN FOUND. TO JUSTIFY THE CARS BEHAVIOR I WAS INSTEAD FALSELY ACCUSED OF MISHANDLING THE CAR ON NUMEROUS OCCASIONS AND PROVIDED PAPERWORK THAT CLAIMED IT WAS NORMAL FOR FORDS WITH ELECTRONIC POWER STEERING (EPAS/PDC) TO DRIFT AROUND THE ROAD ON THEIR OWN AND THAT IT WAS NOT A SAFETY CONCERN. THIS IS ONE OF FOUR COMPLAINTS WITH THIS CAR THAT HAVE NOT BEEN RESOLVED.

NHTSA ODI #11013463

26,260 miles · Jul 20, 2017
Electronic Stability Control (esc)SteeringSuspensionCrash

I WAS DRIVING MY 2016 MUSTANG GT BASE MODEL DOWN A STRAIGHT ROAD WITH THE TRACTION CONTROL "ON" AND THE CAR RANDOMLY LOCKED ALL OF THE WHEELS AND TURNED SIDEWAYS INTO ONCOMING TRAFFIC AND ONLY STOPPING WHEN I HIT A CURB. WHILE SLIDING THERE WAS NO THROTTLE OR BRAKE CONTROL BECAUSE THE TRACTION SYSTEM LOCKED ALL FOUR WHEELS. I WE…

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I WAS DRIVING MY 2016 MUSTANG GT BASE MODEL DOWN A STRAIGHT ROAD WITH THE TRACTION CONTROL "ON" AND THE CAR RANDOMLY LOCKED ALL OF THE WHEELS AND TURNED SIDEWAYS INTO ONCOMING TRAFFIC AND ONLY STOPPING WHEN I HIT A CURB. WHILE SLIDING THERE WAS NO THROTTLE OR BRAKE CONTROL BECAUSE THE TRACTION SYSTEM LOCKED ALL FOUR WHEELS. I WENT TO THE FORD DEALER PREVIOUS TO THIS INSTANCE TO COMPLAIN THAT THE FRONT SUSPENSION WAS NOISY AND THE VEHICLE WAS HARD TO CONTROL ON CERTAIN ROAD SURFACES AND IT FELT VERY UNSAFE. AFTER GIVING THEM THIS INFORMATION THEY SCHEDULED ME FOR AN APPOINTMENT A WEEK LATER AND LET ME DRIVE OFF. SUBSEQUENT TO SAY, THE VEHICLE TOTALLY LOST CONTROL 3 DAYS BEFORE THE APPOINTMENT. ROAD SURFACE WAS DRY, IT WAS SUNNY 94 DEGREES AND I WAS TRAVELING AT 40MPH ON A STRAIGHT ROAD AND MY VEHICLE HAS 26K MILES. THE NOISE AND CONTROL ISSUE WAS MINISCULE BUT EXISTENT ON THE VEHICLE AT 14K MILES AND ONLY KEPT GETTING WORSE. I NOTIFIED THE DEALER OF THE POSSIBILITY OF A SAFETY ISSUE BECAUSE OF THE CIRCUMSTANCES AND THEY WERE VERY DEFENSIVE AND MORE CONCERNED ABOUT CHARGING ME FOR THE DAMAGES THAT RESULTED FROM THE VEHICLE MALFUNCTION. I REQUESTED THAT THE COMPUTER LOGS BE PRESERVED AND SENT TO FORD AS IT MAY BE A SAFETY ISSUE AND I WAS TOLD THAT THEY WOULD CHARGE ME EXTRA FOR THAT AND THAT IT WOULD BE QUITE EXPENSIVE AS TO DISCOURAGE ME FROM REPORTING IT. I RETAINED A PRINTOUT OF MY INITIAL COMPLAINT THAT WAS DOCUMENTED AT THE DEALER UPON MY INITIAL VISIT. VEHICLE IS CURRENTLY UNDER FACTORY WARRANTY AND IS BEING DIAGNOSED FOR THE FRONT SUSPENSION NOISE ISSUE.

NHTSA ODI #11006567

Official recalls

5

25V614000 · Seat Belts:pretensioner

Sep 12, 2025

Ford Motor Company (Ford) is recalling certain 2015-2017 Mustang vehicles. Water and road salt may corrode the front seat belt anchor pretensioner cables.

Consequence & remedy

Consequence: A corroded cable can break, preventing the seat belt from properly restraining an occupant, and increasing the risk of injury during a crash.

Remedy: Dealers will inspect and replace both front seat belt anchor pretensioner assemblies, as necessary. In addition, dealers will remove sections of the carpet and underlayment that contact the cables. Dealers will also inspect the A-pillar sealing patches, and as necessary, install A-pillar body plugs, and/or inspect and replace the front outboard seat bolts. Repairs will be performed free of charge. Interim letters, notifying owners of the safety risk, were mailed October 20, 2025. Additional letters will be sent once the final remedy is available, anticipated December 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25S92. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov September 17, 2025.

25V572000 · Back Over Prevention: Sensing System: Camera

Sep 3, 2025

Ford Motor Company (Ford) is recalling certain 2015-2019 Lincoln MKC, Mustang, F-350 SD, F-250 SD, F-450 SD, 2015-2017 Lincoln Navigator, Expedition, 2015-2018 Edge, Transit Connect, 2016-2019 F-550 SD, Transit, 2017-2019 Econoline, and 2019 Ranger vehicles. The rearview camera may display a distorted, inverted, or blank image when the vehicle is in reverse.

Consequence & remedy

Consequence: A rearview camera that displays an inverted, distorted, or blank image can reduce the driver’s view behind the vehicle, increasing the risk of a crash.

Remedy: Dealers will inspect and replace the rearview camera as necessary, free of charge. Owner notification letters were mailed January 13, 2026. Ford owners will receive letters in phases, beginning January 2026 and June 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 25S89. This recall expands previous NHTSA recall number 25V270. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning September 8, 2025.

22V082000 · Back Over Prevention: Sensing System: Camera

Feb 16, 2022

Ford Motor Company (Ford) is recalling certain 2015-2017 Mustang vehicles. The rearview camera wiring may be loose or damaged, which can result in a blank or distorted image.

Consequence & remedy

Consequence: A rearview camera that displays a blank or distorted image can reduce the driver's rear view, increasing the risk of a crash.

Remedy: Dealers will inspect and repair the decklid wiring harness and/or replace the rearview camera, as necessary, free of charge. Owner notification letters were mailed December 23, 2022 and June 26, 2023. Remedy parts are expected to become available in the 4th Quarter of 2022. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 22S06.

16V779000 · Engine And Engine Cooling:cooling System:hoses/lines/piping/fittings

Oct 26, 2016

Ford Motor Company (Ford) is recalling certain model year 2015-2017 Mustang vehicles manufactured February 24, 2015, to August 30, 2016. A hose may separate from the engine oil cooler tube assembly causing an oil leak.

Consequence & remedy

Consequence: A sudden loss of engine oil may cause engine failure, increasing the risk of a crash. Additionally, an oil leak, in the presence of an ignition source, increases the risk of a fire.

Remedy: Ford will notify owners, and dealers will replace the engine oil cooler tube assembly, free of charge. The recall began on March 23, 2017. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 16S40.

15V707000 · Child Seat:tether: Connector/clip; Seat Belts

Oct 26, 2015

Ford Motor Company (Ford) is recalling certain model year 2016 Ford Mustang vehicles manufactured September 26, 2015, to October 1, 2015. The front and rear seat belts and child seat tether anchors may have been damaged in shipping from the supplier to the vehicle assembly plant and may not adequately restrain the occupant in a crash. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 208, "Occupant Crash Protection," and 225, "Child restraint anchorage systems."

Consequence & remedy

Consequence: If the restraint components do not function as intended, the occupants may not be properly restrained in the event of a crash, increasing their risk of injury.

Remedy: Ford will notify owners, and dealers will replace the front and rear seat belt assemblies and the child seat tether anchors, free of charge. The recall began on December 18, 2015. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 15C13.

Additional source detail variants (2)

Child Seat:tether: Connector/clip

Ford Motor Company (Ford) is recalling certain model year 2016 Ford Mustang vehicles manufactured September 26, 2015, to October 1, 2015. The front and rear seat belts and child seat tether anchors may have been damaged in shipping from the supplier to the vehicle assembly plant and may not adequately restrain the occupant in a crash. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 208, "Occupant Crash Protection," and 225, "Child restraint anchorage systems."

Consequence: If the restraint components do not function as intended, the occupants may not be properly restrained in the event of a crash, increasing their risk of injury.

Remedy: Ford will notify owners, and dealers will replace the front and rear seat belt assemblies and the child seat tether anchors, free of charge. The recall began on December 18, 2015. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 15C13.

Seat Belts

Ford Motor Company (Ford) is recalling certain model year 2016 Ford Mustang vehicles manufactured September 26, 2015, to October 1, 2015. The front and rear seat belts and child seat tether anchors may have been damaged in shipping from the supplier to the vehicle assembly plant and may not adequately restrain the occupant in a crash. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard numbers 208, "Occupant Crash Protection," and 225, "Child restraint anchorage systems."

Consequence: If the restraint components do not function as intended, the occupants may not be properly restrained in the event of a crash, increasing their risk of injury.

Remedy: Ford will notify owners, and dealers will replace the front and rear seat belt assemblies and the child seat tether anchors, free of charge. The recall began on December 18, 2015. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 15C13.

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

1

EA21002 · Desiccated Air Bag Inflator Rupture

Opened Sep 17, 2021 · No close date supplied

Status: open (inferred from source dates) · Air Bags:frontal:driver Side:inflator Module; Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Additional source detail variants (2)

Air Bags:frontal:driver Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.

Air Bags:frontal:passenger Side:inflator Module

From 2000 through 2017, Takata produced millions of air bag inflators using two types of phase-stabilized ammonium nitrate ("PSAN") propellant -- propellant 2004 and propellant 2004L. After prolonged exposure to high temperature cycles and humidity, inflators using propellant 2004 can degrade, causing the propellant to burn too quickly when ignited. The rapid burning can cause the inflator to rupture during deployment, potentially causing serious or even fatal injury to vehicle occupants. See 2016 Blomquist Report at www.nhtsa.gov/sites/nhtsa.gov/files/documents/expert_report-hrblomquist.pdf.Consequently, all frontal inflators using propellant 2004 that do not contain a "desiccant" (a substance that traps and holds moisture) in US vehicles are under recall. These "non-desiccated" inflators either have been or are required to be replaced.In some cases, the remedy part for these recalled inflators was, or will be, an inflator using either propellant 2004 or 2004L that does contain a desiccant. None of these "desiccated" remedy parts (which were installed in older model year vehicles) are currently under recall for a degradation concern. Certain subsets of desiccated PSAN inflators using propellant 2004 for use as original equipment, however, have been recalled for a degradation concern. All Takata inflators produced with propellant 2004L contain desiccant, and none of these desiccated inflators using propellant 2004L are under recall for a degradation concern. There have been no reported field ruptures in any non-recalled desiccated PSAN inflators.It is understood that desiccants fully saturate at some threshold, at which point any additional moisture will not be captured. This means the degradation process observed in non-desiccated inflators using propellant 2004 may also occur in non-recalled desiccated inflators using propellant 2004, assuming additional moisture enters the inflator and high temperature cycling occurs. Based on available information, desiccant saturation can occur within the first five years in the worst environments, and the time required for full saturation is affected by multiple factors. While no present safety risk has been identified, further work is needed to evaluate the future risk of non-recalled desiccated inflators using propellant 2004.Three entities -- Takata (now known as TK Global), the Independent Testing Coalition, and Exponent -- have been studying the long-term behavior of Takata desiccated PSAN inflators using propellant 2004L (as well as 2004) in the presence of moisture and temperature cycling. The research efforts, which include development of predictive modeling techniques and field sample analysis, are ongoing. To date, none of the researchers have identified field evidence showing that propellant 2004L is undergoing a degradation process that leads to aggressive deployment and potential rupture. However, the time in service of such inflators remains short compared to that of the inflators using propellant 2004. Further study is needed to assess the long-term safety of desiccated inflators using propellant 2004L.The Office of Defects Investigation is opening this investigation to examine whether a safety defect related to propellant degradation exists in non-recalled desiccated PSAN frontal inflators manufactured by Takata. This investigation will require extensive information on Takata production processes and surveys of inflators in the field. Lists of recall actions that may have used desiccated PSAN inflators as remedy parts, as well as the makes and models originally manufactured with them, is available with the downloadable version of this document (see nhtsa.gov/recalls?nhtsaId=EA21002 -- note this information is subject to change/revision as the investigation proceeds). This investigation does not supersede EA15-001, which remains open.