Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
2040–25K
20725–50K
7750–75K
2075–100K
6100–150K
2150K+
516 reports with mileage · 401 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
Electrical System. Review the 391 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Visibility/wiper. Review the 205 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Power Train. Review the 47 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
32 crash reports3 fire reports17 injury reports
What owners actually said
917 reports
46,500 miles · Sep 28, 2020
Visibility
TL* THE CONTACT OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED WHILE DRIVING 30 MPH, WHEN A CRACK APPEARED ON THE FRONT WINDSHIELD. THE CONTACT STATED THAT THE CRACK WAS CAUSED WITHOUT IMPACT. THE VEHICLE WAS NOT DIAGNOSED NOR REPAIRED. A DEALER WAS NOT CONTACTED. THE MANUFACTURER HAD NOT BEEN INFORMED OF FAILURE. THE FAILURE MI…
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TL* THE CONTACT OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED WHILE DRIVING 30 MPH, WHEN A CRACK APPEARED ON THE FRONT WINDSHIELD. THE CONTACT STATED THAT THE CRACK WAS CAUSED WITHOUT IMPACT. THE VEHICLE WAS NOT DIAGNOSED NOR REPAIRED. A DEALER WAS NOT CONTACTED. THE MANUFACTURER HAD NOT BEEN INFORMED OF FAILURE. THE FAILURE MILEAGE WAS APPROXIMATELY 46,500.
NHTSA ODI #11361516
Mileage unknown · Sep 27, 2020
Visibility/wiperCrash
THE WINDSHIELD CRACKED AFTER A COLLISION TO A DEAR. THE CRACK HAS BEEN PROGRESSIVELY GETTING WORSE
NHTSA ODI #11361422
Mileage unknown · Sep 26, 2020
Unknown Or Other
WINDSHIELD CHIPS/CRACKS WITH NO KNOWN CAUSE.
NHTSA ODI #11361271
75,600 miles · Sep 18, 2020
Visibility/wiper
WHILE DRIVING MY NORMAL WORK COMMUTE DOWN A STRAIGHT STRETCH OF ROAD AT 47MPH'NO ROCKS SEEN OR OTHER CARS PRESENT'MY WINDSHIELD SUDDENLY CRACKED 12 INCHES, FOR NO APPARENT REASON. LAST WEEK'IN A COMPLETELY DIFFERENT SPOT'THE WINDSHIELD GOT A LARGE CHIP IN IT FROM A TINY PEBBLE FLUNG UP BY A TRUCK. I JUST BOUGHT THIS CAR FROM SUB…
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WHILE DRIVING MY NORMAL WORK COMMUTE DOWN A STRAIGHT STRETCH OF ROAD AT 47MPH'NO ROCKS SEEN OR OTHER CARS PRESENT'MY WINDSHIELD SUDDENLY CRACKED 12 INCHES, FOR NO APPARENT REASON. LAST WEEK'IN A COMPLETELY DIFFERENT SPOT'THE WINDSHIELD GOT A LARGE CHIP IN IT FROM A TINY PEBBLE FLUNG UP BY A TRUCK. I JUST BOUGHT THIS CAR FROM SUBARU DEALERSHIP 1 MONTH AGO. IT SEEMS HIGHLY LIKELY THAT I WILL HE INJURED FROM THE FAULTY WINDSHIELD IN AN ACCIDENT, FROM A ROCK, OR FOR NO APPARENT REASON. SUBARU DENIED THERE WAS IN ISSUE DESPITE A CLASS ACTION SUIT IN NEW JERSEY, AND TONS OF OTHER COMPLAINTS. DESPITE RESEARCH, I HAD NO IDEA THIS WAS AN ISSUE WITH MY MODEL OR I WOULD NOT HAVE PURCHASED.
NHTSA ODI #11355708
43,000 miles · Sep 16, 2020
Visibility/wiper
WINDSHIELD CRACK ON 2017 SUBARU OUTBACK REQUIRING THOUSANDS IN REPAIR. THE REPAIR WINDSHIELD CONTAINS THE SAME DEFECT. THERE WAS NO INDICATION OF A ROCK OR ANYTHING HITTING THE WINDSHIELD.
NHTSA ODI #11355474
66,000 miles · Sep 16, 2020
Visibility
TL* THE CONTACT'S WIFE OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED WHILE HIS WIFE WAS DRIVING 35 MPH THROUGH A CONSTRUCTION ZONE, AN OBJECT HIT THE LOWER LEFT DRIVER'S SIDE WINDSHIELD WHICH LEFT TWO IMPRINTS ON THE WINDSHIELD. OVER TIME, THE WINDSHIELD CRACKED AND SPREAD ACROSS THE WINDSHIELD. THE CONTACT STATED THAT THE WIND…
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TL* THE CONTACT'S WIFE OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED WHILE HIS WIFE WAS DRIVING 35 MPH THROUGH A CONSTRUCTION ZONE, AN OBJECT HIT THE LOWER LEFT DRIVER'S SIDE WINDSHIELD WHICH LEFT TWO IMPRINTS ON THE WINDSHIELD. OVER TIME, THE WINDSHIELD CRACKED AND SPREAD ACROSS THE WINDSHIELD. THE CONTACT STATED THAT THE WINDSHIELD GLASS WAS POORLY MANUFACTURED AND THAT THE SIZE OF THE OBJECT THAT HIT HIS WIFE'S WINDSHIELD SHOULD NOT HAVE CAUSED THAT SEVERE OF DAMAGE. THE CONTACT ALSO STATED THAT THE CRACK THAT FORMED OVER THE WINDSHIELD HAD OBSTRUCTED HIS WIFE'S VISION WHILE DRIVING. ROY ROBINSON SUBARU (6001 33RD AVE NE, MARYSVILLE, WA 98271) WAS NOTIFIED OF THE FAILURE AND THEY REFERRED THE CONTACT TO AN INDEPENDENT GLASS CENTER TO REPLACE THE WINDSHIELD. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS APPROXIMATELY 66,000.
NHTSA ODI #11355440
342 miles · Sep 16, 2020
Visibility/wiper
TL* THE CONTACT OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED THAT WHILE DRIVING AT 35 MPH, THE VEHICLE IN FRONT OF HIM HAD KICKED UP A ROCK THAT HIT HIS PASSENGER WINDSHIELD. DUE TO THE ROCK HITTING THE WINDSHIELD, A CRACK FORMED ON THE PASSENGER SIDE WINDSHIELD. WITHIN 3 DAYS, THE CRACK SPREAD THROUGHOUT THE ENTIRE WINDSHIELD…
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TL* THE CONTACT OWNS A 2017 SUBARU OUTBACK. THE CONTACT STATED THAT WHILE DRIVING AT 35 MPH, THE VEHICLE IN FRONT OF HIM HAD KICKED UP A ROCK THAT HIT HIS PASSENGER WINDSHIELD. DUE TO THE ROCK HITTING THE WINDSHIELD, A CRACK FORMED ON THE PASSENGER SIDE WINDSHIELD. WITHIN 3 DAYS, THE CRACK SPREAD THROUGHOUT THE ENTIRE WINDSHIELD. THE CONTACT STATED THAT THE WINDSHIELD GLASS WAS POORLY DESIGNED AND THAT THE SIZE OF THE ROCK THAT HIT HIS WINDSHIELD SHOULD NOT HAVE CAUSED THAT SEVERE OF DAMAGE. THE CONTACT ALSO STATED THAT THE CRACK THAT FORMED OVER THE WINDSHIELD HAD OBSTRUCTED HIS VISION WHILE DRIVING. THE CONTACT CALLED THE MANUFACTURER WHO DIRECTED TO A WINDSHIELD SUPPLIER FOR ASSISTANCE. THE CONTACT HAD TO WAIT ABOUT 4 MONTHS TO HAVE HIS WINDSHIELD REPLACED. THE VEHICLE HAD BEEN REPAIRED. THE FAILURE MILEAGE WAS 342.
NHTSA ODI #11355437
Mileage unknown · Sep 15, 2020
Electrical System
IN NOVEMBER 2019 I HAD TO REPLACE MY BATTERY WHICH WAS REPLACED FOR FREE BY SUBARU IN CHANDLER, AZ AND WAS GUARANTEED FOR 30 MONTHS, IN SEPTEMBER 2020, I HAD TO REPLACE MY BATTERY AGAIN WHICH WAS INSTALLED BY SUBARU IN CHANDLER, AZ FOR FREE AND GUARANTEED FOR 30 MONTHS. I DID A SEARCH ON FAULTY BATTERIES ON SUBARU AND FOUND THE …
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IN NOVEMBER 2019 I HAD TO REPLACE MY BATTERY WHICH WAS REPLACED FOR FREE BY SUBARU IN CHANDLER, AZ AND WAS GUARANTEED FOR 30 MONTHS, IN SEPTEMBER 2020, I HAD TO REPLACE MY BATTERY AGAIN WHICH WAS INSTALLED BY SUBARU IN CHANDLER, AZ FOR FREE AND GUARANTEED FOR 30 MONTHS. I DID A SEARCH ON FAULTY BATTERIES ON SUBARU AND FOUND THE BELOWS INFORMATION.. SO I DECIDED TO FILE A REPORT. " SUBARU IS HIT WITH A NEW LAWSUIT ALLEGING THE 2016-2020 SUBARU OUTBACK AND 2019-2020 ASCENT HAVE DEFECTIVE ELECTRICAL SYSTEMS CAUSING PREMATURE BATTERY FAILURE. WHAT SHOULD OWNERS DO IF YOU ARE EXPERIENCING THE SAME ISSUES?"
NHTSA ODI #11355247
17,000 miles · Sep 14, 2020
Electrical System
BATTERY GOES DEAD OVERNIGHT. IN 2019 I EXPERIENCED A DEAD BATTERY ON MY OUTBACK. IT HAPPENED IN EARLY 2020. I REPLACED THE BATTERY AROUND MAY OF THIS YEAR. I TOOK IT TO LOCAL DEALER AND LEFT FOR 2 DAYS. DEALER UPDATED ECO AND SAID THAT SHOULD FIX IT, FAIL INAGAIN IN JULY 2020 AND AGAIN TODAY 9-15-2020
NHTSA ODI #11354872
38,000 miles · Sep 11, 2020
Electrical System
MULTIPLE BATTERY FAILURES- BATTERY DIES REPEATEDLY. HAVE REPLACED 4 TIMES ALREADY. LAST DEAD BATTERY IS TODAY WITH IT HAVING DIED LAST WEEK AS WELL. THIS WILL BE 3RD BATTERY IN LESS THAN A YEAR.SOMETIMES HEADLIGHT WILL DIMLY FLASH OR THERE WILL BE A THUMPING NOISE THAT COMES FROM THE BACK, POSSIBLY THE TAILGATE. OTHER TIMES IT I…
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MULTIPLE BATTERY FAILURES- BATTERY DIES REPEATEDLY. HAVE REPLACED 4 TIMES ALREADY. LAST DEAD BATTERY IS TODAY WITH IT HAVING DIED LAST WEEK AS WELL. THIS WILL BE 3RD BATTERY IN LESS THAN A YEAR.SOMETIMES HEADLIGHT WILL DIMLY FLASH OR THERE WILL BE A THUMPING NOISE THAT COMES FROM THE BACK, POSSIBLY THE TAILGATE. OTHER TIMES IT IS DEAD NEXT DAY WHEN GOING TO START IT AFTER HAVING BEEN DRIVEN THE PREVIOUS DAY. KEYS ARE NOT KEPT IN CAR.
Subaru of America, Inc. (Subaru) is recalling certain 2016-2017 Outback vehicles. A replacement air bag control module may have been installed that is not compatible with the passenger air bag module, possibly affecting air bag deployment.
Consequence & remedy
Consequence: In the event of a crash necessitating passenger frontal air bag deployment, the air bag may not deploy properly, increasing the risk of injury.
Remedy: Subaru will notify owners, and dealers will replace the passenger air bag module, free of charge. The recall began February 3, 2020. Owners may contact Subaru customer service at 1-844-373-6614. Subaru's number for this recall is WUX-09.
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Legacy and Outback vehicles manufactured September 21, 2016, to September 23, 2016. In the affected vehicles, the knee guard bracket may not be properly attached to the steering beam assembly.
Consequence & remedy
Consequence: If the knee guard is not properly attached and the driver is not wearing a seatbelt, the knee guard may not be able to properly restrain the driver's lower body in the event of a crash, increasing the risk of injury.
Remedy: Subaru will notify owners, and dealers will inspect the knee guard welding on each vehicle's steering beam, replacing the beam as necessary, free of charge. The recall began November 14, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTL-72.
Additional source detail variants (2)
Air Bags:knee Bolster
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Legacy and Outback vehicles manufactured September 21, 2016, to September 23, 2016. In the affected vehicles, the knee guard bracket may not be properly attached to the steering beam assembly.
Consequence: If the knee guard is not properly attached and the driver is not wearing a seatbelt, the knee guard may not be able to properly restrain the driver's lower body in the event of a crash, increasing the risk of injury.
Remedy: Subaru will notify owners, and dealers will inspect the knee guard welding on each vehicle's steering beam, replacing the beam as necessary, free of charge. The recall began November 14, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTL-72.
Steering:column
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Legacy and Outback vehicles manufactured September 21, 2016, to September 23, 2016. In the affected vehicles, the knee guard bracket may not be properly attached to the steering beam assembly.
Consequence: If the knee guard is not properly attached and the driver is not wearing a seatbelt, the knee guard may not be able to properly restrain the driver's lower body in the event of a crash, increasing the risk of injury.
Remedy: Subaru will notify owners, and dealers will inspect the knee guard welding on each vehicle's steering beam, replacing the beam as necessary, free of charge. The recall began November 14, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTL-72.
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Outback vehicles manufactured June 20, 2016, to June 23, 2016. The affected vehicles may have improperly tightened attaching bolts for the front left and right brake calipers, wheel hubs, and the right stabilizer clamp.
Consequence & remedy
Consequence: If any of the front brake caliper, wheel hub or stabilizer clamp attaching bolts loosen or detach, the related components would also become loose and may detach possibly making the vehicle unstable and reducing the braking capability. These conditions would increase the risk of a crash.
Remedy: Subaru has notified owners, and dealers will inspect the bolts for proper torque, and replace any loose bolts, free of charge. The recall began on August 8, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTE-66.
Additional source detail variants (2)
Service Brakes, Hydraulic:foundation Components:disc:caliper
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Outback vehicles manufactured June 20, 2016, to June 23, 2016. The affected vehicles may have improperly tightened attaching bolts for the front left and right brake calipers, wheel hubs, and the right stabilizer clamp.
Consequence: If any of the front brake caliper, wheel hub or stabilizer clamp attaching bolts loosen or detach, the related components would also become loose and may detach possibly making the vehicle unstable and reducing the braking capability. These conditions would increase the risk of a crash.
Remedy: Subaru has notified owners, and dealers will inspect the bolts for proper torque, and replace any loose bolts, free of charge. The recall began on August 8, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTE-66.
Suspension
Subaru of America, Inc. (Subaru) is recalling certain model year 2017 Outback vehicles manufactured June 20, 2016, to June 23, 2016. The affected vehicles may have improperly tightened attaching bolts for the front left and right brake calipers, wheel hubs, and the right stabilizer clamp.
Consequence: If any of the front brake caliper, wheel hub or stabilizer clamp attaching bolts loosen or detach, the related components would also become loose and may detach possibly making the vehicle unstable and reducing the braking capability. These conditions would increase the risk of a crash.
Remedy: Subaru has notified owners, and dealers will inspect the bolts for proper torque, and replace any loose bolts, free of charge. The recall began on August 8, 2016. Owners may contact Subaru customer service at 1-800-782-2783. Subaru's number for this recall is WTE-66.
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.
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.