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2015 BMW 428I

Owner reports · Recalls · Investigations

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Counts vary with age, sales and reporting. They are not failure rates.

What owners reported most

All reported categories

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When problems were reported

Mileage at the reported incident

35 reports with mileage · 41 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 35 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine And Engine Cooling. Review the 26 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine. Review the 10 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

10 crash reports4 fire reports6 injury reports

Electrical System complaints

35 reports
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Mileage unknown · Feb 21, 2025
Electrical SystemEngine And Engine Cooling

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine an Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time …

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The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine an Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI #11644122

84,000 miles · Feb 19, 2025
Electrical SystemEngine And Engine Cooling

The contact owns a 2015 BMW 428I. The contact was notified of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was made aware of the issue and confirmed that parts were not yet available. The contact stated that an a…

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The contact owns a 2015 BMW 428I. The contact was notified of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was made aware of the issue and confirmed that parts were not yet available. The contact stated that an abnormal oil burning odor was coming from the vehicle. The check engine warning light became illuminated. The vehicle was taken to an independent mechanic, and it was discovered that there was oil leaking from the gasket and onto the bank 1 sensor, which caused the sensor to become corroded. The mechanic linked the failure to the recall. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The vehicle was taken to a dealer and the contact was provided an estimate for a diagnostic test. The contact stated that the vehicle was not repaired, and the engine was overheating. The failure mileage was approximately 84,000. VIN tool confirms parts not available.

NHTSA ODI #11643733

61,000 miles · Feb 19, 2025
Electrical SystemEngine And Engine Cooling

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The contact stated that while driving at an undisclosed speed, there was white smoke coming from under the hood. …

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The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The contact stated that while driving at an undisclosed speed, there was white smoke coming from under the hood. No warning light was illuminated. The local dealer was contacted. 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 61,000. VIN tool confirms parts not available.

NHTSA ODI #11643663

Mileage unknown · Jan 23, 2025
Electrical SystemEngine And Engine Cooling

The contact's daughter owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was contacted. The contact stated that the manufacturer had exceeded a reasonable amo…

Read full complaint

The contact's daughter owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was not yet available. The local dealer was contacted. 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 issue. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI #11638020

Mileage unknown · Jan 2, 2025
Electrical SystemEngine And Engine Cooling

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was…

Read full complaint

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The dealer was contacted and confirmed that parts were not yet available. The manufacturer was not made aware of the issue. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI #11633749

70,000 miles · Dec 30, 2024
Electrical SystemEngine And Engine Cooling

The contact owns a 2014 BMW 428I. The contact stated while driving at an undisclosed speed, the contact noticed a smoky odor coming from the vehicle and the contact noticed smoke coming from the engine compartment. The contact pulled the vehicle over and turned the vehicle off. The vehicle was able to restart. The contact receiv…

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The contact owns a 2014 BMW 428I. The contact stated while driving at an undisclosed speed, the contact noticed a smoky odor coming from the vehicle and the contact noticed smoke coming from the engine compartment. The contact pulled the vehicle over and turned the vehicle off. The vehicle was able to restart. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was unavailable. The dealer was contacted. The vehicle was not diagnosed or repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the failure. The approximate failure mileage was 70,000. VIN tool confirms parts not available.

NHTSA ODI #11633230

Mileage unknown · Nov 12, 2024
Electrical System

The water pump electrical connector on my 2015 BMW 428i failed, as identified in Recall Campaign No. 24V-608. This defect caused repeated engine overheating, leading to damage to the oil pan gasket and valve cover gaskets. An independent service center confirmed the damage was due to overheating from the faulty water pump. The…

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The water pump electrical connector on my 2015 BMW 428i failed, as identified in Recall Campaign No. 24V-608. This defect caused repeated engine overheating, leading to damage to the oil pan gasket and valve cover gaskets. An independent service center confirmed the damage was due to overheating from the faulty water pump. The issue has worsened, with a visible oil leak contributing to frequent engine overheating, making it unsafe to drive long distances. Contact Timeline: 1.October 10, 2024: I received the recall notice from BMW for the defective water pump electrical connector. 2.October 24, 2024: I emailed BMW [XXX] and [XXX] ) to report the overheating and related damage, requesting a full inspection and repairs. 3.October 2024: I visited an independent body shop, which confirmed the damage, and later the BMW dealership in Pompano Beach, which also confirmed the issues but did not agree to cover the repairs under the recall. 4.November 8, 2024: BMW Recall Support Services confirmed the recall is open but did not address the additional damage. 5.November 11, 2024: Robert Pfeiffer from BMW left a voicemail, only noting a delay in parts but not addressing my concerns about the damage. 6.November 12, 2024: I called Robert Pfeiffer but was unable to reach him and left a voicemail. I followed up with an email, reiterating my request for BMW to cover the related repairs due to the worsening vehicle condition. Current Concern: The oil leak continues to worsen, increasing engine overheating risk. No warning lamps initially appeared, but symptoms began shortly after the recall notice. Both the independent body shop and the BMW dealership confirmed the overheating and gasket damage. I request NHTSA’s assistance, as BMW has not resolved the issue despite the clear link to the defective part. The vehicle is available for inspection, and this problem presents a serious safety risk. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI #11624758

Mileage unknown · Nov 7, 2024
Electrical SystemStructure

Water accumulation in the rear passenger side when it rains. Can hear slushing water when driving. It accumulated all the way to the luggage compartment and caused the Control unit rear electrical and the ASD module to fail causing $2564.61 in repairs. Was wondering if this is the case of the issue [XXX] . When I read online th…

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Water accumulation in the rear passenger side when it rains. Can hear slushing water when driving. It accumulated all the way to the luggage compartment and caused the Control unit rear electrical and the ASD module to fail causing $2564.61 in repairs. Was wondering if this is the case of the issue [XXX] . When I read online there Is a lot of complaints about this. Has BMW ever acknowledged the issue? [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI #11624085

Mileage unknown · Oct 24, 2024
Electrical SystemEngine And Engine Cooling

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufactur…

Read full complaint

The contact owns a 2015 BMW 428I. The contact received notification of NHTSA Campaign Number: 24V608000 (Engine and Engine Cooling, Electrical System); however, the part to do the recall repair was unavailable. 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 issue. The contact had not experienced a failure. VIN tool confirms parts not available.

NHTSA ODI #11621696

75,000 miles · Aug 30, 2021
Electrical SystemTiresFire

The contact owned a 2015 BMW 428i. The contact stated that while driving approximately 50 MPH, the vehicle drove over a pot and the air pressure monitoring system warning had displayed. After stopping the vehicle, flames and smoke were present coming from the front driver side wheel well. The fire department was called to the sc…

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The contact owned a 2015 BMW 428i. The contact stated that while driving approximately 50 MPH, the vehicle drove over a pot and the air pressure monitoring system warning had displayed. After stopping the vehicle, flames and smoke were present coming from the front driver side wheel well. The fire department was called to the scene but the vehicle was completely engulfed in flames and was destroyed. The cause of the failure was not determined due to the extent of the fire damage. A police report was taken and the vehicle was towed away. The manufacturer was contacted regarding the failure. The local dealer was not contacted. The failure mileage was 75,000.

NHTSA ODI #11431012

Official recalls

5

24V608000 · Electrical System:wiring:connectors/plugs/receptacles; Engine And Engine Cooling:cooling System:pump

Aug 13, 2024

BMW of North America, LLC. (BMW) is recalling certain 2012-2015 X1 sDrive28i, X1 xDrive28i, 2012-2016 Z4 sDrive28i, 528i, 528i xDrive, 328i, 328xi, 2016-2018 X5 xdrive 40e, 2014-2016 228i, 228xi, 428i, 428i xDrive, 328xi Gran Turismo, 2013-2017 X3 sDrive28i, X3 xDrive28i, 2015-2018 X4 xDrive28i, 2015-2016 428xi vehicles. An improperly sealed electrical connector on the water pump may be exposed to water and short circuit.

Consequence & remedy

Consequence: An electrical short increases the risk of a fire.

Remedy: Dealers will inspect and replace the water pump and plug connector as necessary, and install a protective shield, free of charge. Owner notification letters were mailed on March 28, 2025. Owners may contact BMW customer service at 1-800-525-7417.

Additional source detail variants (2)

Electrical System:wiring:connectors/plugs/receptacles

BMW of North America, LLC. (BMW) is recalling certain 2012-2015 X1 sDrive28i, X1 xDrive28i, 2012-2016 Z4 sDrive28i, 528i, 528i xDrive, 328i, 328xi, 2016-2018 X5 xdrive 40e, 2014-2016 228i, 228xi, 428i, 428i xDrive, 328xi Gran Turismo, 2013-2017 X3 sDrive28i, X3 xDrive28i, 2015-2018 X4 xDrive28i, 2015-2016 428xi vehicles. An improperly sealed electrical connector on the water pump may be exposed to water and short circuit.

Consequence: An electrical short increases the risk of a fire.

Remedy: Dealers will inspect and replace the water pump and plug connector as necessary, and install a protective shield, free of charge. Owner notification letters were mailed on March 28, 2025. Owners may contact BMW customer service at 1-800-525-7417.

Engine And Engine Cooling:cooling System:pump

BMW of North America, LLC. (BMW) is recalling certain 2012-2015 X1 sDrive28i, X1 xDrive28i, 2012-2016 Z4 sDrive28i, 528i, 528i xDrive, 328i, 328xi, 2016-2018 X5 xdrive 40e, 2014-2016 228i, 228xi, 428i, 428i xDrive, 328xi Gran Turismo, 2013-2017 X3 sDrive28i, X3 xDrive28i, 2015-2018 X4 xDrive28i, 2015-2016 428xi vehicles. An improperly sealed electrical connector on the water pump may be exposed to water and short circuit.

Consequence: An electrical short increases the risk of a fire.

Remedy: Dealers will inspect and replace the water pump and plug connector as necessary, and install a protective shield, free of charge. Owner notification letters were mailed on March 28, 2025. Owners may contact BMW customer service at 1-800-525-7417.

24V527000 · Air Bags:frontal:driver Side:inflator Module

Jul 11, 2024

BMW of North America, LLC (BMW) is recalling certain 2015 6 Series Gran Coupe, 2014 5 Series Gran Turismo, 2014 5 Series Sedan, 2015 6 Series Convertible, 2015 6 Series Coupe, 2014 X5, 2013-2014 X3, 2014-2015 3 Series Sedan, 2014 4 Series Coupe, 2014 4 Series Convertible, 2014 3 Series Gran Turismo, and 2015 4 Series Gran Coupe vehicles. Please see the recall report for the complete list of models. The driver's air bag inflator may explode during deployment, due to a manufacturing defect.

Consequence & remedy

Consequence: An inflator explosion may result in sharp metal fragments striking the driver or other occupants, increasing the risk of injury or death.

Remedy: The driver's front air bag will be replaced, free of charge. Owner notification letters were mailed September 6, 2024. Owners may contact BMW customer service at 1-800-525-7417.

24V288000 · Air Bags:side/window

Apr 24, 2024

BMW of North America, LLC (BMW) is recalling certain 2014-2015 2 Series Coupe (228i, 228i xDrive, M235i), 3 Series Sedan (320i, 320i xDrive, 328i, 328i xDrive, 335i, 335i xDrive, M3, 328d, 328d xDrive), 4 Series Coupe (428i, 428i xDrive, 435i, 435i xDrive, M4), and 2015 4 Series Gran Coupe (428i, 428i xDrive, 435i, 435i xDrive) vehicles. The head air bag inflator may fail at the weld joint, which can cause gas to leak from the inflator or result in an inflator rupture.

Consequence & remedy

Consequence: An inflator that ruptures may cause sharp metal fragments to enter or exit the vehicle, increasing the risk of injury. Additionally, an inflator that leaks gas may only partially inflate during a crash, increasing the risk of injury.

Remedy: Dealers will replace the head air bags, free of charge. Owner notification letters were mailed November 4, 2024. Owners may contact BMW customer service at 1-800-525-7417.

15V189000 · Fuel System, Gasoline:delivery:fuel Pump

Mar 31, 2015

BMW of North America LLC (BMW) is recalling certain model year 2014 228i Coupe, M235i Coupe, 320i, 320xi, 328i, 328xi, 335i, 335xi, ActiveHybrid 3, 328xi Sports Wagon, 428i Coupe, 428xi Coupe, 435i Coupe, 435xi Coupe, 428i Convertible, 428xi Convertible, 435i Convertible, 328xi Gran Turismo, 335xi Gran Turismo, and 2015 428i Gran Coupe, 428xi Gran Coupe, and 435i Gran Coupe vehicles. Improper nickel plating of components within the fuel pump may result in the fuel pump failing.

Consequence & remedy

Consequence: If the fuel pump fails, the vehicle may stall without warning, increasing the risk of a crash.

Remedy: BMW will notify owners, and dealers will replace the fuel pump, free of charge. Owners were mailed interim notices on May 28, 2015. The recall began on July 6, 2015. Owners may contact BMW customer service at 1-800-525-7417.

15V148000 · Air Bags

Mar 13, 2015

BMW of North America, LLC (BMW) is recalling certain model year 2015 428i Convertible, 428i xDrive Convertible, 435i Convertible, and 435i xDrive Convertible vehicles manufactured October 22, 2014, to February 27, 2015. Due to a programming error, the driver's front air bag deployment timing may be incorrect. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) No. 208, "Occupant Crash Protection."

Consequence & remedy

Consequence: If the driver's front air bag deployment timing is incorrect, there is an increased risk of personal injury in the event of a vehicle crash.

Remedy: BMW will notify owners, and dealers will reprogram the air bag control module with corrected software version, free of charge. The recall began May 11, 2015. Owners may contact BMW customer service at 1-800-525-7417.

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.