IllustrationHigh pressure fuel pump failure. I was driving down the road when it stalled with no warning whatsoever and it put itself in park in the middle of the road, I had five other people with me that were put in serious danger. The dealership confirmed that it was in dead the problem, but there was no warning light nothing whatsoever.
2015 BMW X5
Owner reports · Recalls · Investigations
Similar to other model years
Owner complaints for the 2015 BMW X5 do not stand out strongly from the model-year median of 100.5.
About this comparison →How this year compares
Owner complaints by model year
Compare all X5 years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
120–25K
925–50K
1650–75K
1275–100K
15100–150K
7150K+
71 reports with mileage · 81 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 42 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Fuel/propulsion System. Review the 30 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Fuel System, Diesel. Review the 20 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 reports7 fire reports5 injury reports
What owners actually said
152 reportsI have owned the above-identified 2015 BMW XDrive 35d since new. This vehicle is equipped with BMW’s N57T engine. My wife and I started experiencing the car pulsing or surging under acceleration within the first year of ownership. Despite no warning lights being on, we brought the car to the dealership as early as September 20, …
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I have owned the above-identified 2015 BMW XDrive 35d since new. This vehicle is equipped with BMW’s N57T engine. My wife and I started experiencing the car pulsing or surging under acceleration within the first year of ownership. Despite no warning lights being on, we brought the car to the dealership as early as September 20, 2016, to complain of the pulsating acceleration on the car. Although we experienced the problem daily, the dealership was “unable to duplicate the problem.” We visited the dealership several times thereafter to complain of this ongoing problem. Each time the dealership was “unable to duplicate the problem.” Finally, in June 2018, I visited the dealership and asked to go for a ride with the head service tech. During that drive, I was able to easily duplicate the issue. Upon further investigation by the head service tech, on or about June 11, 2018, BMWNA replaced a fuel injector (injector No. 6, PN 13-53-8-506-548) on the vehicle under warranty, which finally remedied the nearly two-year problem. In October 2021, the vehicle’s check engine light started going on and off intermittently. As a result, on or about October 14, 2021, my wife took the car to the dealership. We were informed that fuel injector No. 2 was now bad and that it would cost us nearly $1,250 to repair the vehicle. Given that one fuel injector on the vehicle had previously failed, I started doing some research about this engine and its fuel injectors. What I discovered was very troubling. In 2019, BMW of North America (“BMWNA”) issued SIB 01 09 19 (DC 13 53 90 06 00) extending the warranty on the fuel injectors used in certain models equipped with the N57T engine to 10 years/120,000 miles. Specifically, BMWNA listed the following vehicles as being covered by the SIB: F02 (740Ld xDrive) (N57T Engine) Model Year 2015 produced from 2/13/2014 to 5/08/2015F10 (535d Sedan) (N57T Engine) Model Year 2015 produced from 7/07/2014 to 6/26/2015F10 (535d xDrive Sedan) (N57T Engine) M
Hi, here to report and solicit the assistance of the NHTSA to keep us safe. Thanks for everything you do! Our 2015 X5 (F15) diesel with the N57T motor had check engine light illuminate @~61k miles while driving normally at surface street speeds. This was within one-month of BMW performing its second mandatory EGR cooler recall…
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Hi, here to report and solicit the assistance of the NHTSA to keep us safe. Thanks for everything you do! Our 2015 X5 (F15) diesel with the N57T motor had check engine light illuminate @~61k miles while driving normally at surface street speeds. This was within one-month of BMW performing its second mandatory EGR cooler recall (once in 2020 and again in 2023), NHTSA Campaign Number 21V907000 for fire potential. BMW dealership advised the check engine was due to fuel injector #6 failure. I asked the dealership if this (could) be related to the recent EGR replacement they performed and was advised no. The EGR cooler and fuel injectors are DIRECTLY related, so this was surprising. Furthermore, there are loads of forums online that point to this, plus two active, safety recalls for the N57T motors including fuel injectors and the high pressure fuel pump (HPFP). My biggest concern is BMWs HPFP Safety Recall SIB130121 affecting 2014-2018 N57T motors - issued on 7/29/21 (coincidently, my birthday;-) It's dangerous that BMW will not proactively replace the HPFP, even when experiencing ongoing fuel system issues (2x EGR coolers and now injectors) that may be tied to a potential HPFP failure. I won't wait for a catastrophic failure for what is an existing and well known recall. This is well documented across forums so it's concerning the NHTSA OK'd BMW's 10yr/120k mile "warranty extension" vs full, mandatory recall. BMW should be accountable and replace the HPFP before catastrophic power loss occurs at the wrong time/wrong place. When it does, I wanted to ensure this record was on file with you agency for insurance purposes. Second concern is for sib010919. Injector recall is for 2016&17 X5 diesels with the N57T engine, plus other diesel models from 2015/16&17. Online, deep-dive research revealed a gap, where the 2015 X5 diesels (again with the N57T motor) were excluded. While this is not a severe as the HPFP, can the agency advise why 2015's were missed? Many thanks!!
so i was driving at 70 mph on the highway and my front wheel driveshaft broke and hit the transmission with a potential chance to have and accident, i was researching and bmw x5 have a recall of those shaft up to 2013 and if i don't mistaking same part number as mine.
1. What component or system failed or malfunctioned, and is it available for inspection upon request? The Air Suspension Compressor needs to be remove and replace. Left Rear Air Bag is Leaking. Tires have 3/32nds tread remaining which is unsafe. 2. How was your safety or the safety of others put at risk? Might cause accident whe…
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1. What component or system failed or malfunctioned, and is it available for inspection upon request? The Air Suspension Compressor needs to be remove and replace. Left Rear Air Bag is Leaking. Tires have 3/32nds tread remaining which is unsafe. 2. How was your safety or the safety of others put at risk? Might cause accident when driving especially in freeway. 3. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, confirmed by an independent service center. 4. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes, confirmed by an independent service center. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No warning messages.
passenger seat restraint system
The contact owns a 2015 BMW X5. The contact stated that after activating the passenger’s side indicator, the exterior turn signal operated as designed; however, the instrument panel light failed to illuminate. The vehicle was taken to the dealer to be diagnosed and the contact was informed that the instrument cluster needed to b…
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The contact owns a 2015 BMW X5. The contact stated that after activating the passenger’s side indicator, the exterior turn signal operated as designed; however, the instrument panel light failed to illuminate. The vehicle was taken to the dealer to be diagnosed and the contact was informed that the instrument cluster needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The approximate failure mileage was 37,000.
The contact owns a 2015 BMW X5. The contact received notification of NHTSA Campaign Number: 21V907000 (Fuel System, Diesel) however, the part to do the recall repair was not yet available. The contact stated that the vehicle was overheating, and the A/C was inoperable. There was no warning light illuminated. The local dealer was…
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The contact owns a 2015 BMW X5. The contact received notification of NHTSA Campaign Number: 21V907000 (Fuel System, Diesel) however, the part to do the recall repair was not yet available. The contact stated that the vehicle was overheating, and the A/C was inoperable. There was no warning light illuminated. The local dealer was contacted, and the vehicle was diagnosed but no issues were found. The vehicle was not repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was not made aware of the failure. The failure mileage was approximately 20,000. Parts distribution disconnect. The consumer stated the dealer was contacted multiple times but no repairs were made.
I received a warning light and checked with my OBDII reader that the Diesel Exhaust Fluid transfer pump had a implausible reading and was not working. This is a key part of the Selective Catalytic Reduction (SCR) system, part of the emissions control system, and will make the vehicle fault to the point where it will lock the car…
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I received a warning light and checked with my OBDII reader that the Diesel Exhaust Fluid transfer pump had a implausible reading and was not working. This is a key part of the Selective Catalytic Reduction (SCR) system, part of the emissions control system, and will make the vehicle fault to the point where it will lock the car from being driven (no start condition).
Some engine rumbling at normal operation, and noticed a yellow check-engine light, not filled (meaning not a catastrophic issue). Attached my OBDII reader and found error: 24BF00 Injector, cylinder 2, zero-quantity adaptation - permitted filtered actuation duration correction too high. A google search confirmed this fault is co…
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Some engine rumbling at normal operation, and noticed a yellow check-engine light, not filled (meaning not a catastrophic issue). Attached my OBDII reader and found error: 24BF00 Injector, cylinder 2, zero-quantity adaptation - permitted filtered actuation duration correction too high. A google search confirmed this fault is covered in https://static.nhtsa.gov/odi/tsbs/2020/MC-10184567-9999.pdf with BMW, but my model year and vehicle is not included. I have an F15, 2015 X5, build date 12/2014. This year is covered on other vehicles with the same N57 engine, and so I would suspect that the same issue plaguing the same engine on other models should be applicable here. I would like consideration for additional model years to be added to the SIB.
Official recalls
621V907000 · Fuel System, Diesel
Nov 19, 2021
BMW of North America, LLC (BMW) is recalling certain 2013-2018 328d, 328d xDrive, 2014-2018 328d Sports Wagon, 328d xDrive Sports Wagon, 2014-2016 535d, 535d xDrive, 2015 740Ld xDrive, 2015-2017 X3 xDrive28d SAV, and 2014-2017 X5 xDrive35d SAV diesel vehicles equipped with an Exhaust Gas Recirculation (EGR) module with an integrated cooler. The EGR cooler may leak internally, causing coolant to mix with diesel engine soot, which could result in smoldering particles and a melting intake manifold.
Consequence & remedy
Consequence: A melting intake manifold increases the risk of a fire.
Remedy: Dealers will replace the EGR cooler and inspect the intake manifold, replacing it as necessary, free of charge. This recall includes all vehicles previously recalled under 18V-755. Vehicles previously recalled under 18V-755 will need to have the new remedy performed for this recall. An interim owner notification letter was mailed on January 18, 2022. The remedy is expected to be available in June 2022. Owner notification letters were mailed on July 6, 2022. Owners may contact BMW customer service at 1-800-525-7417.
21V586000 · Fuel System, Diesel:delivery:fuel Pump
Jul 29, 2021
BMW of North America, LLC (BMW) is recalling certain 2014-2018 328d, 328d xDrive, X5 xDrive35d, 2014-2016 535d, 535d xDrive, 2015 740Ld xDrive, and 2015-2017 X3 xDrive28d vehicles. The high-pressure fuel pump may fail.
Consequence & remedy
Consequence: Fuel pump failure can cause an engine stall while driving, increasing the risk of a crash.
Remedy: Dealers will replace the high-pressure fuel pump, free of charge. Owner notification letters were mailed on January 14, 2022. Owners may contact BMW customer service at 1-800-525-7417.
18V755000 · Engine And Engine Cooling:exhaust System:emission Control:gas Recirculation Valve (egr Valve)
Oct 25, 2018
BMW of North America, LLC (BMW) is recalling certain 2013-2018 BMW 328d and 328d xDrive, 2014-2018 328d Sports Wagon and 328d xDrive Sports Wagon, 2014-2016 535d and 535d xDrive, 2015 740Ld xDrive, 2015-2017 X3 xDrive28d SAV and 2014-2017 X5 xDrive35d SAV vehicles equipped with an Exhaust Gas Recirculation (EGR) module with an integrated cooler. If the EGR cooler leaks internally, the coolant can mix with diesel engine soot. The high EGR temperatures may result in these particles possibly smoldering and melting the intake manifold.
Consequence & remedy
Consequence: The melting intake manifold can increase the risk of a fire.
Remedy: BMW will notify owners, and dealers will inspect and replace the EGR cooler as necessary. If a leak has already occurred, the engine intake manifold will also be replaced. These repairs will be made free of charge. The recall began May 13, 2019. Owners may contact BMW customer service at 1-800-525-7417.
16V683000 · Air Bags:frontal:driver Side:inflator Module
Sep 21, 2016
BMW of North America, LLC. (BMW) is recalling certain model year 2015 BMW X3 sDrive28i, X3 xDrive28i, X3 xDrive35i, X3 xDrive28d, X4 xDrive28i and X4 xDrive35i vehicles, and model year 2014-2015 X5 xDrive35i, X5 sDrive35i, X5 xDrive50i, and 2014 X5 xDrive35d vehicles. The affected vehicles have a driver's frontal air bag inflator that may have been improperly welded.
Consequence & remedy
Consequence: In the event of a crash necessitating deployment of the driver's frontal air bag, the inflator housing could separate from the base plate and result in metal striking the vehicle occupants, potentially resulting in serious injury or death.
Remedy: BMW will notify owners, and dealers will replace the driver's front air bag, free of charge. The recall began on November 1, 2016. Owners may contact BMW customer service at 1-800-525-7417.
15V147000 · Air Bags
Mar 13, 2015
BMW of North America, LLC (BMW) is recalling certain model year 2015 BMW X5 xDrive 35d Sports Activity Vehicles (SAV) manufactured August 19, 2014, to February 16, 2015, and 2014-2015 BMW X5 xDrive 35i, X5 sDrive 35i, X5 xDrive 50i, Sports Activity Vehicles (SAV) manufactured August 28, 2013, to February 16, 2015. In the affected vehicles, the Head Protection System (HPS) air bag may not be securely connected to the air bag inflator gas generator.
Consequence & remedy
Consequence: Without a secure connection to the inflator, the HPS air bags may have insufficient inflation during a vehicle crash, increasing the risk of injury.
Remedy: BMW will notify owners, and dealers will replace the Head Protection System, free of charge. The recall began on June 24, 2015. Owners may contact BMW customer service at 1-800-525-7417.
14V650000 · Seats
Oct 17, 2014
BMW of North America, LLC (BMW) is recalling certain model year 2015 X5 vehicles manufactured September 12, 2014,to September 21, 2014 and equipped with the optional rear comfort seat. The left rear seat belt attachment point in the affected vehicles may not have been sufficiently welded.
Consequence & remedy
Consequence: In the event of a crash, the seat belt attachment could break and fail to restrain a seat occupant, increasing the risk of injury.
Remedy: BMW will notify owners, and dealers will replace the left rear seat frame, free of charge. The recall began November 2014. Owners may contact BMW customer service at 1-800-525-7417 or CustomerRelations@bmwusa.com.
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
2EA23001 · High Pressure Fuel Pump Failure
Opened Mar 17, 2023 · No close date supplied
Status: open (inferred from source dates) · Fuel System, Diesel:delivery:fuel Pump
The Office of Defects Investigation (ODI) opened PE21-021 on October 14, 2021, to investigate incidents alleging a stall/loss of motive power as a result of high-pressure fuel pump failures in certain model year (MY) 2019-2020 Ram 2500, 3500, 4500, and 5500 heavy duty trucks equipped with 6.7L Cummins turbodiesel engines. During the investigation, ODI sought to determine if the related defect allegation was limited in scope to the recalled population. After review of information request response materials from both FCA and BMW, NHTSA determined that sufficient information to identify a comprehensive recall population could not be produced by FCA and BMW.During the investigation FCA filed recalls 22V406, 22E048, 22V767, and 22E087 which include vehicles not identified in the initial subject population by ODI. ODI also received recall 21V586, involving loss of motive power due to failed CP4 fuel pumps on certain BMW manufactured vehicles. An information request letter response received from BMW indicated that failed pumps on their vehicles were caused by an interaction between pump internal components and US market diesel fuel, leading to increased slip and eventual particle-generating wear surface. Additional work will be done to identify whether a similar root cause is associated with the FCA recalled population and if similar wear dynamics occur on pumps supplied to vehicle manufacturers other than those included in the recalled population.ODI has upgraded this investigation to an EA in order to 1) determine engineering specifications of internal pump components that are correlated with pump failure leading to loss of motive power or other safety related hazards, 2) identify vehicle populations equipped with alleged defective pump variants, 3) assess if vehicles equipped with alleged defective pump variants result in an unreasonable risk to motor vehicle safety and 4) gather and review any other relevant information related to high pressure fuel pump failure associated with the subject populations of recalls 21V586, 21V880, 21E094, 22V406, 22E048, 22V767, and 22E087.Review of the above information will allow NHTSA to confirm root cause and recall remedy viability, and identify and evaluate vehicle populations equipped with pump components that may pose an unreasonable risk to motor vehicle safety.The ODI reports cited above can be reviewed at: http://www-odi.nhtsa.dot.gov/owners/SearchNHTSAID using the following complaint identification numbers: 11257550, 11351441, 11361603, 11361616, 11365300, 11365426, 11365858, 11366401, 11372337, 11373793, 11374797, 11376793, 11377871, 11378173, 11384377, 11386063, 11387018, 11399710, 11402550, 11415339, 11418868, 11418870, 11427075, 11434276, 11436807, 11437226, 11437249, 11437273, 11437292, 11437294, 11437394, 11437399, 11437403, 11437405, 11437423, 11437528, 11437565, 11437579, 11437580, 11437590, 11437679, 11437744, 11437781, 11437842, 11437993, 11438006, 11438008, 11438121, 11438138, 11438155, 11438392, 11438629, 11439359, 11439879, 11440397, 11443030, 11446542, 11448163, 11453556, 11458918, 11460558, 11469337
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.