NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
510 reports47,000 miles · Jul 10, 2018
Engine
WE NOTICED AN EXHAUST LEAK (NOISY) ON OUR 2015 OUTBACK, UPON INSPECTION BY THE DEALER THEY DETERMINED THE CATALYTIC CONVERTER NEEDED TO BE REPLACED, THEY INITIALLY REJECTED OUR WARANTEE CLAIM BECAUSE SUBARU AUTHORIZES REPLACEMENT ONLY IF A MIL IS PRESENT. AFTER SOME DISCUSSION THE DEALER (SUBARU) AGREED TO REPLACE AS "GOOD WILL…
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WE NOTICED AN EXHAUST LEAK (NOISY) ON OUR 2015 OUTBACK, UPON INSPECTION BY THE DEALER THEY DETERMINED THE CATALYTIC CONVERTER NEEDED TO BE REPLACED, THEY INITIALLY REJECTED OUR WARANTEE CLAIM BECAUSE SUBARU AUTHORIZES REPLACEMENT ONLY IF A MIL IS PRESENT. AFTER SOME DISCUSSION THE DEALER (SUBARU) AGREED TO REPLACE AS "GOOD WILL". WE LIVE IN THE NORTHEAST AND IT SEEMS ROAD SALT AND SAND CAUSE THE CONVERTER TO RUST PREMATURELY, THE LOCATION OF THE CONVERTED IS AFT OF THE EXHAUST MANIFOLD AND AT THE BASE OF THE PASSENGER COMPARTMENT, THERE IS A RISK OF CARBON MONOXIDE POISONING WITH THESE TYPES OF LEAKS, AND IT IS UNHEARD OF THAT THESE PARTS FAIL AFTER THREE YEARS.
NHTSA ODI #11110458
35,000 miles · Jul 10, 2018
Power Train
SUBJECT 2015 OUTBACK CVT TRANSMISSION LURCHES AND BOGS DURING ACCELERATION, WE HAVE TRIED WORKING WITH SUBARU FOR REPAIR HOWEVER, THEY CONSIDER THE UNIT AS WORKING TO WITHIN STANDARD AND WILL NOT REPLACE UNLESS IT FAILS COMPLETELY.
NHTSA ODI #11110454
46,000 miles · Jul 10, 2018
Visibility/wiper
IN JUNE OF 2018 OUR FRONT WINDSHIELD DEVELOPED A CRACK ACROSS THE TOP DRIVER SIDE, THERE IS NO EVIDENCE OF ANY SORT OF IMPACT TO THE WINDSHIELD AND THE CRACK SPREAD ACROSS THE ENTIRE WINDSHIELD OVER A NUMBER OF DAY. SUBARU REJECTED OUR WARANTEE CLAIM BECAUSE THE CRACK WAS IN THE WRONG LOCATION.
NHTSA ODI #11110450
45,000 miles · Jun 15, 2018
Wheels
RIGHT REAR WHEEL BEARING FAILURE AT 45,000 MILES. LOUD GRINDING, THEN THUMPING NOISES WHEN AUTO IN MOTION
NHTSA ODI #11102153
44,000 miles · Jun 9, 2018
EngineService BrakesUnknown Or Other
WHILE PARKING THE CAR AT AN OPEN PARKING LOT IN SHOPPING CENTER AT LOW SPEED (<5MPH) THE ENGINE SURGED SUDDENLY AND THE VEHICLE ACCELERATED UNCONTROLLABLY. IT REQUIRED TREMENDOUS PRESSURE ON BRAKE TO EVENTUALLY OVERRIDE THE ENGINE.
NHTSA ODI #11100658
24,000 miles · May 25, 2018
Power TrainSuspension
TL* THE CONTACT OWNS A 2015 SUBARU OUTBACK. WHILE DRIVING 35 MPH, THE VEHICLE'S WHEELS SEIZED AND THE VEHICLE JERKED VIOLENTLY. THE FAILURE OCCURRED WITHOUT WARNING. THE VEHICLE WAS TOWED TO SUBARU OF LAS VEGAS (6455 W ROY HORN WAY, LAS VEGAS, NV 89118) WHERE IT WAS DIAGNOSED THAT CV AXLES AND THE TRANSMISSION FAILED AND NEEDED …
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TL* THE CONTACT OWNS A 2015 SUBARU OUTBACK. WHILE DRIVING 35 MPH, THE VEHICLE'S WHEELS SEIZED AND THE VEHICLE JERKED VIOLENTLY. THE FAILURE OCCURRED WITHOUT WARNING. THE VEHICLE WAS TOWED TO SUBARU OF LAS VEGAS (6455 W ROY HORN WAY, LAS VEGAS, NV 89118) WHERE IT WAS DIAGNOSED THAT CV AXLES AND THE TRANSMISSION FAILED AND NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 24,000.
NHTSA ODI #11097971
57,000 miles · May 21, 2018
Electrical System
MY CAR WAS PARKED AT A PIER. GOT INTO CAR AND WOULD NOT START. DID NOT SEEM LIKE A BATTERY ISSUE, HOWEVER, AS IT SOUNDED AS IF IT WOULD START TO TURN OVER, BUT THEN JUST CLICKED OFF. THEN I PUSHED THE BUTTON TO THE DRIVER'S SEAT WINDOW AND IT GOT STUCK HALF WAY UP, BUT THE OTHER WINDOWS WERE OKAY AT THAT TIME. THEN THE WHEE…
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MY CAR WAS PARKED AT A PIER. GOT INTO CAR AND WOULD NOT START. DID NOT SEEM LIKE A BATTERY ISSUE, HOWEVER, AS IT SOUNDED AS IF IT WOULD START TO TURN OVER, BUT THEN JUST CLICKED OFF. THEN I PUSHED THE BUTTON TO THE DRIVER'S SEAT WINDOW AND IT GOT STUCK HALF WAY UP, BUT THE OTHER WINDOWS WERE OKAY AT THAT TIME. THEN THE WHEEL LOCKED UP AND THE BREAK WOULD NOT BUDGE. THEN AFTER TRYING TO TURN THE CAR ON AGAIN, THE OTHER WINDOWS STOPPED WORKING. EACH TIME BEFORE TRYING TO START IT AGAIN, I WAITED A FEW MINUTES. THEN AFTER TRYING TO START THE CAR AGAIN, ALL THE LOCKS FROZE AND WE WERE STUCK INSIDE THE VEHICLE! INSIDE LOCKS AND LEVER DID NOT WORK! LUCKILY, THE DRIVER'S SEAT WINDOW WAS STUCK HALF WAY DOWN, SO I TOOK MY MANUAL KEY OUT OF THE ACCESS KEY, AND STUCK MY HAND AND ARM OUT THE WINDOW TO OPEN THE CAR FROM THE OUTSIDE. IT WAS ALSO LUCK THAT MY FRIEND WAS WITH ME, AS SHE HAD TO PULL THE INSIDE KNOB AT THE SAME TIME (AS I COULD NOT REACH IT) SO I COULD OPEN THE DOOR. THEN 2 MEN WALKED BY AND OFFERED THEIR ASSISTANCE. WHERE ABLE TO JUMP START THE CAR AND GET IT GOING. THE PROBLEM STILL WAS NOT SOLVED, HOWEVER, AS NOW MY PARKING BREAK WAS STUCK ON AND I COULD NOT TURN IT OFF. THEN I INADVERTENTLY TURNED THE CAR OFF, AND IT MIRACULOUSLY TURNED RIGHT BACK ON AND ALL SOFTWARE DEFICIENCIES WERE CLEARED SO I WAS ABLE TO DRIVE HOME. THIS ALL HAPPENED OVER A PERIOD OF 5 HOURS, DURING WHICH TIME I HAD CALLED AAA FOR A TOW, MY EX-HUSBAND FOR A RIDE (AS AAA WOULD NOT ALLOW MY DOG TO RIDE IN THE TOW TRUCK) AND I WAS 1HR 20 MIN FROM HOME WHICH AS THE EVENING CREPT IN, WAS SLOWLY BECOMING AN UNSAFE AREA AND WE WERE GETTING MORE AND MORE SCARED. WHAT IF I HAD BEEN ALONE? WHAT IF MY WINDOW WAS NOT HALF WAY DOWN? WHAT IF I HAD BROKEN DOWN IN AN UNSAFE PLACE FROM THE GET GO? THIS CAR IS UNSAFE TO DRIVE!
NHTSA ODI #11097025
30,000 miles · May 19, 2018
EnginePower TrainUnknown Or Other
AFTER 2 YEARS OF OWNERSHIP ON MY BRAND NEW SUBARU OUTBACK 2015, I HAVE NOTICED A LOUD SQUEAKY SOUND COMING FROM THE ENGINE WHEN I START MY CAR AFTER IT RAINED/SNOWED. THE SOUND WOULD GO AWAY AFTER A FEW MINUTES, HOWEVER, IT DIDN'T SEEM NORMAL. I TOOK THE CAR TO THE DEALERSHIP TO HAVE IT CHECKED OUT. THE DEALERSHIP TOLD ME THAT N…
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AFTER 2 YEARS OF OWNERSHIP ON MY BRAND NEW SUBARU OUTBACK 2015, I HAVE NOTICED A LOUD SQUEAKY SOUND COMING FROM THE ENGINE WHEN I START MY CAR AFTER IT RAINED/SNOWED. THE SOUND WOULD GO AWAY AFTER A FEW MINUTES, HOWEVER, IT DIDN'T SEEM NORMAL. I TOOK THE CAR TO THE DEALERSHIP TO HAVE IT CHECKED OUT. THE DEALERSHIP TOLD ME THAT NOTHING IS WRONG AND IT IS PERFECTLY FINE. HOWEVER, THE SQUEAKY NOISE STILL OCCURS AFTER RAIN/SNOW. IT SEEMS TO ME THAT WATER IS LEAKING INTO A BELT WHEN IT'S NOT SUPPOSE TO AND IT IS CAUSING THE NOISE WHEN THE ENGINE IS STARTED. SUBARU NEEDS TO LOOK INTO THIS ISSUE BECAUSE THIS PROBLEM ONLY HAPPENS AFTER IT RAINS/SNOWS AND CANNOT BE REPLICATED WHEN THE CAR IS BROUGHT TO THE DEALERSHIP. THEREFORE, IT IS HARD TO HAVE THIS ISSUE FIXED.
NHTSA ODI #11096820
Mileage unknown · Apr 3, 2018
EngineEquipment
2015 SUBARU OUTBACK. CONSUMER WRITES IN REGARDS TO ROUGH IDLING IN VEHICLE. *LD THE CONSUMER STATED THE VEHICLE ANNOYINGLY VIBRATED WHEN THE AIR CONDITIONER WAS ON. *JS
NHTSA ODI #11032394
35,000 miles · Mar 27, 2018
Electrical System
BATTERY PERIODICALLY GOES DEAD OVERNIGHT
NHTSA ODI #11081529
Official recalls
5May 11, 2016
Subaru of America, Inc. (Subaru) is recalling certain model year 2016-2017 Legacy and Outback vehicles manufactured February 29, 2016, to May 6, 2016. The steering column on the affected vehicles may have been improperly machined, and as a result, turning the steering wheel may have no effect on the direction of the wheels.
Consequence & remedy
Consequence: The loss of steering ability would increase the risk of a crash.
Remedy: Subaru will notify owners, and dealers will inspect the lot number on the steering column, replacing the steering column, as necessary, free of charge. The recall began May 13, 2016. Owners may contact Subaru customer service at 1-800-782-2783 or by visiting http://www.wtd65.service-campaign.com. Subaru's number for this recall is WTD-65. Note: Until the vehicles have been inspected, owners are advised not to drive their vehicles.
Apr 27, 2016
Subaru of America, Inc. (Subaru) is recalling certain model year 2015 Legacy and Outback vehicles manufactured on July 20, 2015. The brake fluid used in these vehicles may contain excess moisture which may adversely affect the performance of the electronic stability control system. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 126, "Electronic Stability Control Systems."
Consequence & remedy
Consequence: Poor performance of the electronic stability control system when it is activated may result in a loss of vehicle control, increasing the risk of a crash.
Remedy: Subaru will notify owners, and dealers will perform an ABS activation, then flush and replace the brake fluid, free of charge. The recall began on May 20, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTC-64.
Aug 10, 2015
Subaru of America, Inc. (Subaru) is recalling certain 2015 and 2016 model year Subaru Legacy 4-Door and Outback vehicles manufactured July 3, 2015, to July 27, 2015. Transmission oil may leak from a deformed seal cap on the propeller shaft yoke.
Consequence & remedy
Consequence: If the transmission oil leaks onto the exhaust pipe, there is a possible risk of fire.
Remedy: Subaru will notify owners, and dealers will replace the propeller shaft, free of charge. The recall began on August 28, 2015. Owners may contact 1-800-782-2783. Subaru's number for this recall is WQU-56.
Additional source detail variants (2)
Power Train:driveline:driveshaft
Subaru of America, Inc. (Subaru) is recalling certain 2015 and 2016 model year Subaru Legacy 4-Door and Outback vehicles manufactured July 3, 2015, to July 27, 2015. Transmission oil may leak from a deformed seal cap on the propeller shaft yoke.
Consequence: If the transmission oil leaks onto the exhaust pipe, there is a possible risk of fire.
Remedy: Subaru will notify owners, and dealers will replace the propeller shaft, free of charge. The recall began on August 28, 2015. Owners may contact 1-800-782-2783. Subaru's number for this recall is WQU-56.
Power Train:automatic Transmission
Subaru of America, Inc. (Subaru) is recalling certain 2015 and 2016 model year Subaru Legacy 4-Door and Outback vehicles manufactured July 3, 2015, to July 27, 2015. Transmission oil may leak from a deformed seal cap on the propeller shaft yoke.
Consequence: If the transmission oil leaks onto the exhaust pipe, there is a possible risk of fire.
Remedy: Subaru will notify owners, and dealers will replace the propeller shaft, free of charge. The recall began on August 28, 2015. Owners may contact 1-800-782-2783. Subaru's number for this recall is WQU-56.
Jun 12, 2015
Subaru of America, Inc. (Subaru) is recalling certain model year 2015 Legacy vehicles manufactured March 10, 2014, to April 16, 2015, Outback vehicles manufactured February 24, 2014, to April 16, 2015, Impreza vehicles manufactured September 9, 2014, to April 14, 2015, XV Crosstrek vehicles manufactured October 16, 2014, to April 15, 2015, and 2016 WRX vehicles manufactured March 23, 2015, and equipped with the Eyesight Driver Assist System. If the switch that activates the brake lights fails, the automatic pre-collision braking component of the driver assist system will not function.
Consequence & remedy
Consequence: If the automatic pre-collision braking system does not function as intended, the vehicle will not react to an obstacle in its path, increasing the risk of a crash.
Remedy: Subaru will notify owners, and dealers will reprogram the driver assist system, free of charge. The recall began on July 20, 2015. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WQS-54.
Additional source detail variants (2)
Forward Collision Avoidance: Crash Imminent Braking
Subaru of America, Inc. (Subaru) is recalling certain model year 2015 Legacy vehicles manufactured March 10, 2014, to April 16, 2015, Outback vehicles manufactured February 24, 2014, to April 16, 2015, Impreza vehicles manufactured September 9, 2014, to April 14, 2015, XV Crosstrek vehicles manufactured October 16, 2014, to April 15, 2015, and 2016 WRX vehicles manufactured March 23, 2015, and equipped with the Eyesight Driver Assist System. If the switch that activates the brake lights fails, the automatic pre-collision braking component of the driver assist system will not function.
Consequence: If the automatic pre-collision braking system does not function as intended, the vehicle will not react to an obstacle in its path, increasing the risk of a crash.
Remedy: Subaru will notify owners, and dealers will reprogram the driver assist system, free of charge. The recall began on July 20, 2015. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WQS-54.
Exterior Lighting:brake Lights:switch
Subaru of America, Inc. (Subaru) is recalling certain model year 2015 Legacy vehicles manufactured March 10, 2014, to April 16, 2015, Outback vehicles manufactured February 24, 2014, to April 16, 2015, Impreza vehicles manufactured September 9, 2014, to April 14, 2015, XV Crosstrek vehicles manufactured October 16, 2014, to April 15, 2015, and 2016 WRX vehicles manufactured March 23, 2015, and equipped with the Eyesight Driver Assist System. If the switch that activates the brake lights fails, the automatic pre-collision braking component of the driver assist system will not function.
Consequence: If the automatic pre-collision braking system does not function as intended, the vehicle will not react to an obstacle in its path, increasing the risk of a crash.
Remedy: Subaru will notify owners, and dealers will reprogram the driver assist system, free of charge. The recall began on July 20, 2015. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WQS-54.
Sep 19, 2014
Subaru of America, Inc. (Subaru) is recalling certain model year 2015 Outback vehicles manufactured January 22, 2014, to August 18, 2014, and equipped with a Subaru accessory trailer hitch assembly. During installation, the trailer hitch mounting nuts may have been overtightened, potentially resulting in failure of the trailer hitch mounting studs.
Consequence & remedy
Consequence: The mounting nut(s) may not provide sufficient force to remain attached to the studs or the studs themselves might break. If this were to happen while a trailer is being towed, the driver might not be able to operate the vehicle as desired or the trailer may detach from the vehicle. Either situation could increase the risk of a crash.
Remedy: Subaru will notify owners, and dealers will replace all eight mounting nuts for the trailer hitch assembly, and will inspect all eight mounting studs for damage, free of charge. The recall began on October 7, 2014. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WQN-50.
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
1EA21002 · 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.