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2014 Toyota Sienna

Owner reports · Recalls · Investigations

Similar to other model years

Owner complaints for the 2014 Toyota Sienna do not stand out strongly from the model-year median of 183.

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When problems were reported

Mileage at the reported incident

104 reports with mileage · 59 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.

  • Structure. Review the 44 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 16 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Air Bags. Review the 13 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

6 crash reports2 fire reports3 injury reports

Structure complaints

44 reports
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Mileage unknown · Dec 30, 2025
Structure

The passenger-side power sliding door system failed to stop or reverse when it encountered physical interference with the vehicle’s open fuel door. The door continued opening under power despite clear obstruction by a fixed exterior body component. The affected components, including the sliding door mechanism and damaged fuel do…

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The passenger-side power sliding door system failed to stop or reverse when it encountered physical interference with the vehicle’s open fuel door. The door continued opening under power despite clear obstruction by a fixed exterior body component. The affected components, including the sliding door mechanism and damaged fuel door latch, remain available for inspection upon request. A powered sliding door continuing to operate against an obstruction creates a foreseeable risk of injury to occupants or bystanders, as well as vehicle damage. If a person’s hand, arm, or clothing had been in the same position as the fuel door, injury could have occurred. The incident occurred during normal vehicle use and demonstrates inadequate safeguards against obstruction. The issue has been formally reproduced or confirmed by an independent service center which noted that the incident occurred as described during normal operation of the power sliding door, and no abnormal conditions were present at the time. No warning lamps, messages, or other symptoms appeared prior to the incident. The power sliding door operated normally and without indication of malfunction until it failed to stop when encountering the open fuel door. Fueling the vehicle with the fuel door open is routine and expected vehicle use. The absence of any interlock, sensor logic, or safeguard preventing a powered sliding door from operating against an open body panel represents a design deficiency rather than a maintenance or wear issue. This condition may affect other vehicles equipped with similar power sliding door systems and warrants evaluation.

NHTSA ODI #11707717

99,500 miles · Sep 5, 2025
EngineStructure

The contact owns a 2014 Toyota Sienna. The contact stated that while driving 70 MPH, there was an audible alarm coming from the vehicle, alerting the contact that the door was ajar. The passenger’s side slide door opened independently while the vehicle was in motion. The vehicle was modified to accommodate a ramp for the contact…

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The contact owns a 2014 Toyota Sienna. The contact stated that while driving 70 MPH, there was an audible alarm coming from the vehicle, alerting the contact that the door was ajar. The passenger’s side slide door opened independently while the vehicle was in motion. The vehicle was modified to accommodate a ramp for the contact's two wheel-bound children. The contact pulled over to the side of the road and closed the sliding door. The contact's husband tied the door to prevent it from opening independently again. The check engine warning light was intermittently illuminated. The vehicle was taken to the dealer, where it was inspected. The contact was informed that two latches had corroded and needed to be replaced. The vehicle was not repaired. Upon further investigation, the contact related the failure to NHTSA Campaign Number: 16V858000 (STRUCTURE). However, the VIN was not included. The manufacturer was not made aware of the failure. The failure mileage was approximately 99,500.

NHTSA ODI #11685365

68,000 miles · Oct 31, 2023
Structure

The contact owns a 2014 Toyota Sienna. The contact stated while driving at various speeds, the contact heard abnormal sounds coming from the vehicle. The passenger’s side slide door became inoperable. No warning light was illuminated. The vehicle had not been diagnosed or repaired by an independent mechanic or dealer. The manufa…

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The contact owns a 2014 Toyota Sienna. The contact stated while driving at various speeds, the contact heard abnormal sounds coming from the vehicle. The passenger’s side slide door became inoperable. No warning light was illuminated. The vehicle had not been diagnosed or repaired by an independent mechanic or dealer. The manufacturer was made aware of the failure and advised the contact to call the NHTSA Hotline for assistance. The failure mileage was approximately 68,000.

NHTSA ODI #11552851

Mileage unknown · Sep 6, 2022
Lane DepartureService BrakesStructure

Great coaching

NHTSA ODI #11483120

Mileage unknown · Sep 6, 2022
Forward Collision AvoidanceService BrakesStructure

Good question

NHTSA ODI #11483116

100,000 miles · Apr 9, 2021
Structure

THE DRIVERS SIDE REAR DOOR DOES NOT OPEN PROPERLY ALL THE TIME, IT JAMS PARTIALLY OPEN. THE CAR IS STATIONARY AND NOT MOVING.

NHTSA ODI #11407223

95,000 miles · Jan 6, 2021
Structure

MY SON WAS GETTING INTO THE VAN VIA THE DRIVER SIDE SLIDING DOOR. HIS BACKPACK BUMPED THE SENSOR, AND THE DOOR OPENED AND FROZE HALFWAY OPEN. I DISENGAGED THE AUTOMATIC OPENING, BUT THE DOOR HAD DIFFICULTY CLOSING. I NOTICED THAT THE CABLE TO THE SLIDING DOOR HAD SNAPPED. I WAS EVENTUALLY ABLE TO CLOSE THE DOOR, BUT NOW THE DOOR…

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MY SON WAS GETTING INTO THE VAN VIA THE DRIVER SIDE SLIDING DOOR. HIS BACKPACK BUMPED THE SENSOR, AND THE DOOR OPENED AND FROZE HALFWAY OPEN. I DISENGAGED THE AUTOMATIC OPENING, BUT THE DOOR HAD DIFFICULTY CLOSING. I NOTICED THAT THE CABLE TO THE SLIDING DOOR HAD SNAPPED. I WAS EVENTUALLY ABLE TO CLOSE THE DOOR, BUT NOW THE DOOR WILL NOT OPEN AT ALL.

NHTSA ODI #11386865

86,000 miles · Mar 5, 2020
Structure

ON 12/20/19 IN MY 2014 TOYOTA SIENNA THE SLIDING DOOR NEXT TO MY 3 YEAR OLD OPENED WHILE I WAS DRIVING. I WAS IN THE MIDST OF ACCELERATING AFTER A LIGHT TURNED GREEN WHEN THE CAR STARTED NOTIFYING ME THAT A DOOR WAS AJAR AND THE PASSENGER-SIDE SLIDING DOOR STARTED OPENING. THE DOOR OPENED FULLY AND REMAINED OPEN AS I WAS AT SPEE…

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ON 12/20/19 IN MY 2014 TOYOTA SIENNA THE SLIDING DOOR NEXT TO MY 3 YEAR OLD OPENED WHILE I WAS DRIVING. I WAS IN THE MIDST OF ACCELERATING AFTER A LIGHT TURNED GREEN WHEN THE CAR STARTED NOTIFYING ME THAT A DOOR WAS AJAR AND THE PASSENGER-SIDE SLIDING DOOR STARTED OPENING. THE DOOR OPENED FULLY AND REMAINED OPEN AS I WAS AT SPEED IN THE MIDDLE OF AN INTERSECTION. NOTE THAT ALL DOORS WERE CLOSED AND LATCHED BEFORE I PUT THE VEHICLE IN DRIVE, AND THIS ONLY OCCURRED AFTER A FEW MILES OF DRIVING. I TOOK THE CAR TO THE DEALERSHIP AND THEY REPLACED THE LATCH ASSEMBLY IN BOTH SLIDING DOORS. THE DEALERSHIP COULDN'T TELL ME WHAT FAILED OR IF THE REPLACED LATCHES WOULD SOLVE THE PROBLEM, SO I CALLED TOYOTA CORP. I LEARNED THAT TOYOTA ALREADY KNEW ABOUT THIS ISSUE. WHEN I ASKED IF THEY COULD ASSURE ME THAT THE SLIDING DOORS WOULDN'T OPEN WHILE DRIVING AGAIN, THEY COULDN'T. THEY TOLD ME THAT THEY COULDN'T CONFIRM THAT THE LATCHES WERE THE PROBLEM, AND WHILE THE REPLACEMENT LATCH HAS A DIFFERENT MODEL NUMBER THAN THE ORIGINAL, THEY DON'T KNOW IF IT IS IN FACT A DIFFERENT PART AND IF SO, HOW. THE ONLY ASSURANCE THAT TOYOTA COULD GIVE ME IS THAT 'OF THE PEOPLE IN YOUR REGION THAT THIS HAS HAPPENED TO, IT HASN'T HAPPENED A SECOND TIME THAT WE KNOW OF'. THE MORE QUESTIONS I ASKED, THE CLEARER IT BECAME THAT THIS COULD HAPPEN AGAIN. PLEASE NOTE THAT THIS ISSUE IS ENTIRELY DIFFERENT FROM THE '16 RECALL THAT INVOLVED SLIDING DOORS OPENING WHILE DRIVING (ALL ASSOCIATED RECALLS HAD BEEN PERFORMED BY TOYOTA DEALERSHIPS PRIOR TO THIS INCIDENT). WE HAD NOT PREVIOUSLY REPORTED THIS TO NHSA AS WE HAD ASSUMED THAT TOYOTA REPORTED THIS INCIDENT AS PART OF OUR CASE WITH THEM.

NHTSA ODI #11316311

70,000 miles · Sep 16, 2019
Structure

TL* THE CONTACT OWNS A 2014 TOYOTA SIENNA. THE CONTACT STATED THAT THE VEHICLE'S SLIDING DOOR FAILED TO FUNCTION WHEN USING THE POWER BUTTON. THE CONTACT HAD TO MANUALLY OPEN AND CLOSE THE SLIDING DOOR FROM THE EXTERIOR HANDLE. THE VEHICLE WAS NOT TAKEN TO A DEALER OR AN INDEPENDENT MECHANIC FOR DIAGNOSTIC TESTING. THE VEHICLE W…

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TL* THE CONTACT OWNS A 2014 TOYOTA SIENNA. THE CONTACT STATED THAT THE VEHICLE'S SLIDING DOOR FAILED TO FUNCTION WHEN USING THE POWER BUTTON. THE CONTACT HAD TO MANUALLY OPEN AND CLOSE THE SLIDING DOOR FROM THE EXTERIOR HANDLE. THE VEHICLE WAS NOT TAKEN TO A DEALER OR AN INDEPENDENT MECHANIC FOR DIAGNOSTIC TESTING. THE VEHICLE WAS INCLUDED IN NHTSA CAMPAIGN NUMBER: 16V858000 (STRUCTURE). THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE APPROXIMATE FAILURE MILEAGE WAS 70,000.

NHTSA ODI #11255564

Mileage unknown · Dec 14, 2018
Structure

MY CAR HAS BOTH SIDES POWER SLINGING DOOR IS UNABLE TO BE OPENED AND CLOSED WHEN COMMANDED.

NHTSA ODI #11161412

Official recalls

6

19V553000 · Service Brakes, Hydraulic:foundation Components:hoses, Lines/piping, And Fittings

Jul 25, 2019

Vantage Mobility International, LLC (Vantage) is recalling certain 2012-2018 AMS Genesis wheelchair vans, built on a Toyota Sienna vehicles. The rubber brake hoses that attach to the rear wheel assembly may be too short, causing them to rub against the rear axle trailing arm.

Consequence & remedy

Consequence: The contact may cause failure of the rear brake hoses, resulting in a loss of vehicle control and reduced braking ability, increasing the risk of a crash.

Remedy: Vantage will notify owners, and dealers will install a set of rear brake hoses that will provide the proper clearance, free of charge. The recall began December 16, 2019. Owners may contact Vantage customer service at 1-800-488-9082.

19V410000 · Service Brakes, Hydraulic:foundation Components:hoses, Lines/piping, And Fittings

Jun 4, 2019

Braun Corporation (Braun) is recalling certain 2014-2019 Toyota Sienna mobility van conversions. The brake lines may have incorrect tube nut fittings installed, which may cause a pressure drop within the braking system.

Consequence & remedy

Consequence: The reduction in the braking system pressure may cause a loss of braking power in the rear braking system, increasing the risk of crash.

Remedy: Braun has notified owners, and dealers will install an adaptor to correct the issue, free of charge. The recall began June 25, 2019. Owners may contact Braun customer service at 1-800-488-0359.

19V005000 · Air Bags:frontal:passenger Side:inflator Module

Jan 9, 2019

Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2014-2016 Toyota 4Runner, 2014-2015 Scion xB, Lexus IS350C, IS250C, 2014 Toyota Sienna, Lexus IS-F, and 2014-2017 Lexus GX460 vehicles sold, or ever registered in the states of Alabama, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, South Carolina, Texas, Puerto Rico, American Samoa, Guam, the Northern Mariana Islands (Saipan), and the U.S. Virgin Islands or "Zone A." Toyota is also recalling certain 2011-2013 Toyota Corolla, Corolla Matrix, Lexus IS250, IS350, 2011-2016 4Runner, 2011-2015 Scion xB, Lexus IS350C, IS250C, 2011-2014 Toyota Sienna, Lexus IS-F, 2011-2017 Lexus GX460, and 2011-2012 Lexus ES350 vehicles ever registered in the states of Arizona, Arkansas, Delaware, District of Columbia, Illinois, Indiana, Kansas, Kentucky, Maryland, Missouri, Nebraska, Nevada, New Jersey, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Virginia, and West Virginia or "Zone B." Toyota is also recalling certain 2010-2013 Toyota Corolla, Corolla Matrix, Lexus IS350, 2010-2016 4Runner, 2010-2013 Lexus IS250, 2010-2015 Scion xB, Lexus IS350C, IS250C, 2010-2017 Lexus GX460, 2010-2014 Lexus IS-F, and 2010-2012 Lexus ES350 vehicles ever registered in the states of Alaska, Colorado, Connecticut, Idaho, Iowa, Maine, Massachusetts, Michigan, Minnesota, Montana, New Hampshire, New York, North Dakota, Oregon, Rhode Island, South Dakota, Utah, Vermont, Washington, Wisconsin, and Wyoming or "Zone C." These vehicles are equipped with air bag inflators assembled as part of the passenger frontal air bag modules, used as original equipment or replacement equipment (such as after a vehicle crash necessitating replacement of the original air bags), that may explode due to propellant degradation occurring after long-term exposure to high absolute humidity, temperature and temperature cycling.

Consequence & remedy

Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants resulting in serious injury or death.

Remedy: Toyota will notify owners. Depending on the vehicle model, dealers will replace the front passenger air bag inflator, or replace the air bag assembly. The recall began February 15, 2019. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's numbers for this recall are "Zone A" Toyota: G0P, Lexus: GLG; "Zone B" Toyota: G0R, Lexus GLH; "Zone C" Toyota: H0A, and Lexus: HLA.

16V858000 · Structure:body:door

Nov 29, 2016

Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2011-2016 Toyota Sienna minivans manufactured January 4, 2010, to August 12, 2016. If the power sliding door is unable to be opened when commanded, such as if the door is frozen shut, the door may subsequently open unexpectedly, possibly while the vehicle is moving.

Consequence & remedy

Consequence: If door opens while the vehicle is moving, there would be an increased risk of injury to the vehicle occupants.

Remedy: Toyota will notify owners, and dealers will replace the junction block, rear sliding door wire harnesses, and install two sub wire harnesses, free of charge. The recall began on July 28, 2017. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's number for this recall is G04.

14V576000 · Fuel System, Gasoline:delivery:hoses, Lines/piping, And Fittings

Sep 19, 2014

Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2014 Toyota Avalon, Camry, Sienna, and Highlander and model year 2015 Lexus RX350 vehicles. Fuel may leak from the one of the fuel delivery pipes in the engine compartment.

Consequence & remedy

Consequence: A fuel leak in the presence of an ignition source increases the risk of a fire.

Remedy: Toyota will notify owners, and dealers will replace any of the suspect fuel delivery pipes free of charge. The recall began November 17, 2014. Owners may contact Toyota customer service at 1-800-331-4331.

14V414000 · Power Train:automatic Transmission:gear Position Indication (prndl)

Jul 8, 2014

Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain model year 2014 Sienna vehicles manufactured June 17, 2014, through June 24, 2014. The affected vehicles have a transmission shift control cable whose protective cable sleeve may have been damaged during assembly. This could cause the control cable to bind or separate during gear shift operation causing incorrect gear selection. As such, these vehicles fail to comply with the requirements of the Federal Motor Vehicle Safety Standard No. 102, "Transmission Shift Lever Sequence, Starter Interlock, and Transmission Braking Effect."

Consequence & remedy

Consequence: If the transmission shift cable separates while the vehicle is being driven, the transmission gear selection may not match the indicated gear and the vehicle may move in an unintended or unexpected direction, increasing the risk of a crash. Furthermore, when the driver goes to stop and park the vehicle, despite selecting the 'PARK' position, the transmission may not be in 'PARK.' If the vehicle is not in the 'PARK' position there is a risk the vehicle will roll away as the driver and other occupants exit the vehicle or anytime thereafter. A vehicle rollaway increases the risk of injury to exiting occupants and bystanders.

Remedy: Toyota will notify owners, and dealers will inspect and replace the transmission shift control cable, as necessary, free of charge. The recall began in early August 2014. Owners may contact Toyota customer service at 1-800-331-4331.

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.