NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
212 reports7,719 miles · May 21, 2012
Fuel System, Gasoline
TL* THE CONTACT OWNS A 2007 MERCEDES BENZ C230. THE CONTACT STATED THAT FUEL FUMES WERE EMITTED INTO THE VEHICLE AND THE RESIDENTIAL GARAGE AFTER REFUELING. THE VEHICLE WAS TAKEN TO THE DEALER, WHO DIAGNOSED THAT THE LEFT FUEL SENDING UNIT AND TWO SEALS NEEDED TO BE REPLACED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. T…
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TL* THE CONTACT OWNS A 2007 MERCEDES BENZ C230. THE CONTACT STATED THAT FUEL FUMES WERE EMITTED INTO THE VEHICLE AND THE RESIDENTIAL GARAGE AFTER REFUELING. THE VEHICLE WAS TAKEN TO THE DEALER, WHO DIAGNOSED THAT THE LEFT FUEL SENDING UNIT AND TWO SEALS NEEDED TO BE REPLACED. THE MANUFACTURER WAS NOT MADE AWARE OF THE FAILURE. THE VEHICLE WAS REPAIRED. THE FAILURE MILEAGE WAS 7,719 AND THE CURRENT MILEAGE WAS 18,624. UPDATED 08/28/12*LJ
NHTSA ODI #10459148
55,000 miles · Apr 15, 2012
Power Train
CAR SEEMS TO STAY IN ONE GEAR AND DOES NOT DOWNSHIFT OR UPSHIFT WHEN NEEDED. THE ONLY SOLUTION IS TO STOP CAR, TURN OFF AND RESTART. IT IS A RISK TO ENTER A MAIN ROAD BECAUSE OF NOT KNOWING WHAT GEAR THE AUTO TRANS IS LOCKED OR IF IT WILL SHIFT TO ANOTHER GEAR TO GET UP TO SPEED. DEALER CHECKED CAR ONCE AND SAID THEY COULD NOT F…
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CAR SEEMS TO STAY IN ONE GEAR AND DOES NOT DOWNSHIFT OR UPSHIFT WHEN NEEDED. THE ONLY SOLUTION IS TO STOP CAR, TURN OFF AND RESTART. IT IS A RISK TO ENTER A MAIN ROAD BECAUSE OF NOT KNOWING WHAT GEAR THE AUTO TRANS IS LOCKED OR IF IT WILL SHIFT TO ANOTHER GEAR TO GET UP TO SPEED. DEALER CHECKED CAR ONCE AND SAID THEY COULD NOT FIND ANYTHING WRONG BUT IT SEEMS IT IS A KNOWN ISSUE THE TRANSMISSION PROBLEM FOR THESE MODEL YEAR. *TR
NHTSA ODI #10455294
42,764 miles · Apr 9, 2012
Fuel System, Gasoline
STRONG RAW FUEL ODOR WAS NOTICED AFTER FILL UP ON MULTIPLE OCCASIONS. INVESTIGATION FOUND THAT BOTH THE FUEL PUMP HOUSING AND THE FUEL SENDER HOUSINGS WERE CRACKED ALLOWING RAW FUEL TO LEAK OUT. THIS IS EXACTLY THE SAME AS THE E CLASS RECALL. THIS RECALL NEEDS TO BE EXTENDED TO INCLUDE THE C CLASS AS WELL AS THIS CAR HAS AN IDEN…
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STRONG RAW FUEL ODOR WAS NOTICED AFTER FILL UP ON MULTIPLE OCCASIONS. INVESTIGATION FOUND THAT BOTH THE FUEL PUMP HOUSING AND THE FUEL SENDER HOUSINGS WERE CRACKED ALLOWING RAW FUEL TO LEAK OUT. THIS IS EXACTLY THE SAME AS THE E CLASS RECALL. THIS RECALL NEEDS TO BE EXTENDED TO INCLUDE THE C CLASS AS WELL AS THIS CAR HAS AN IDENTICAL FAILURE MODE. I FOUND THIS ISSUE WAS PREVIOUSLY REPORTED, AND WOULD LIKE TO SECOND THIS NOTED ISSUE. FOR MANY MONTHS HAVE NOTICED STRONG FUEL SMELL FROM LEFT REAR WHEEL WELL WHENEVER TANK IS OVER 3/4 FULL. MB DEALER CONFIRMS ABOVE SIMILAR DIAGNOSIS AND APPROXIMATELY 1K REPAIR COST, GAS IS LEAKING OUT AND POOLING ON TOP OF SENDER UNIT. *TR
NHTSA ODI #10454581
152,803 miles · Mar 20, 2012
Engine And Engine Cooling
DTC 1208 CODE APPEARS. DUE TO POSITIONING OF TIMING CHAIN RELATIVE TO CRANKSHAFT. ENGINE M272 CAUSED BY WORN SPROCKET ON THE BALANCE SHAFT OF ENGINE. MERCEDES HAS REPAIR KIT AVAILABLE BUT HAS MODIFIED THIS PROBLEM ON NEWER VEHICLES. THIS IS A COMMON OCCURRENCE ON THIS ENGINE, AND SHOULD BE PART OF A NATIONAL RECALL COMPAIGN.…
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DTC 1208 CODE APPEARS. DUE TO POSITIONING OF TIMING CHAIN RELATIVE TO CRANKSHAFT. ENGINE M272 CAUSED BY WORN SPROCKET ON THE BALANCE SHAFT OF ENGINE. MERCEDES HAS REPAIR KIT AVAILABLE BUT HAS MODIFIED THIS PROBLEM ON NEWER VEHICLES. THIS IS A COMMON OCCURRENCE ON THIS ENGINE, AND SHOULD BE PART OF A NATIONAL RECALL COMPAIGN. THE INTERNET IS FULL OF COMPLAINTS OVER THIS AND I BELIEVE THERE IS CURRENTLY A CLASS ACTION LAW SUIT ABOUT THIS. *KB
NHTSA ODI #10452459
69,000 miles · Mar 10, 2012
Fuel System, Gasoline
THE LEFT SIDE FUEL SENDING UNIT IS LEAKING GAS. *TR
NHTSA ODI #10451058
45,000 miles · Feb 13, 2012
Engine And Engine CoolingPower Train
VEHICLE SEEMS TO RUN FINE BUT AFTER A COLD MORNING START THE CHECK ENGINE LIGHT ILLUMINATED. AFTER TAKING IT TO THE DEALERSHIP FOR DIAGNOSTICS (TOTALING $105.00) IT WAS REVEALED THAT THE CODE RENDERING THE BALANCE SHAFT OR POSSIBLE BAD SENSOR WAS THE REASON FOR THE CHECK ENGINE LIGHT ILLUMINATING. THE ESTIMATE COST FOR THIS REPA…
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VEHICLE SEEMS TO RUN FINE BUT AFTER A COLD MORNING START THE CHECK ENGINE LIGHT ILLUMINATED. AFTER TAKING IT TO THE DEALERSHIP FOR DIAGNOSTICS (TOTALING $105.00) IT WAS REVEALED THAT THE CODE RENDERING THE BALANCE SHAFT OR POSSIBLE BAD SENSOR WAS THE REASON FOR THE CHECK ENGINE LIGHT ILLUMINATING. THE ESTIMATE COST FOR THIS REPAIR IS RANGING FROM 5 TO 6 GRAND. THIS IS HIGHLY UNACCEPTABLE FOR A VEHICLE WITH ONLY 45,000 MILES. 2007, MERCEDES BENZ, C230, BLACK ON BLACK, THAT HAS BEEN STORED FOR A MAJORITY OF ITS EXISTENCE BECAUSE I AM DEPLOYED OVERSEAS DOES NOT SEND A GOOD IMPRESSION WHEN THE COMPANY WILL NOT ADMIT THAT THERE IS A DEFINITE PROBLEM WITH THIS ENGINE TYPE. IN TODAY'S ECONOMY, CONSUMERS SPEND A LITTLE MORE TO REASSURE THIS TYPE OF REPAIR IS AVOIDED BY PURCHASING A MORE RELIABLE SOURCE OF TRANSPORTATION. I GUESS I SHOULD HAVE PURCHASED A CHEVY OR FORD, AT LEAST THEN I WOULD BE EXPECTING THIS TYPE OF NONSENSE. *TR
NHTSA ODI #10447711
41,000 miles · Jan 7, 2012
Power Train
VEHICLE WOULD NOT SHIFT OUT OF FIRST GEAR. RPMS WERE AT SHIFT LEVEL, THEN ENGINE SHUT DOWN. RESTARTED AND REVVED ENGINE, LOUD WAILING SOUND. CAR WAS TOWED TO MERCEDES BENZ, THEY SAID TRANSMISSION PUMP BAD AS WELL AS TRANSMISSION, NEEDS REPLACING. *TR
NHTSA ODI #10442791
60,000 miles · Nov 26, 2011
Engine And Engine Cooling
ALTHOUGH I NO LONGER HAVE THE VEHICLE AS IT WAS LEASED, AROUND A YEAR, A YEAR AND 4 MONTHS AGO, MY MERCEDES BENZ WAS MAKING A WEIRD NOISE FROM THE ENGINE AS WELL SO MY CHECK ENGINE LIGHT HAD BEEN ON FOR WEEKS/MONTHS. WHEN I TOOK IT INTO A MB DEALERSHIP THEY HAD TO FIRST GET MY APPROVAL TO TAKE APART THE ENGINE TO DIAGNOSE THE P…
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ALTHOUGH I NO LONGER HAVE THE VEHICLE AS IT WAS LEASED, AROUND A YEAR, A YEAR AND 4 MONTHS AGO, MY MERCEDES BENZ WAS MAKING A WEIRD NOISE FROM THE ENGINE AS WELL SO MY CHECK ENGINE LIGHT HAD BEEN ON FOR WEEKS/MONTHS. WHEN I TOOK IT INTO A MB DEALERSHIP THEY HAD TO FIRST GET MY APPROVAL TO TAKE APART THE ENGINE TO DIAGNOSE THE PROBLEM, OF COURSE I SAID OK SINCE IT WAS A LEASED CAR. ONCE THEY FOUND OUT THE PROBLEM THEY SUGGESTED I NEEDED A NEW ENGINE BASED ON A PROBLEM W/ THE CYLINDERS AND THAT THE FACT I HADN'T GIVEN THE VEHICLE THE PROPER OIL CHANGES, HOWEVER I BELIEVE IT WAS A PROBLEM CAUSED BY THE BALANCE SHIFT GEARS. SO THEY TOLD ME THAT IT WAS GOING TO COST ME AROUND $7000 TO FIX THE PROBLEM BY PUTTING IN A BRAND NEW ENGINE, I ASKED IF MB COULD HELP W/ THE COST BUT THEY REFUSED, CLAIMING THAT SINCE I DIDN'T HAVE A RECORD OF SUFFICIENT OIL CHANGES THEY WOULDN'T HELP....SO I HAD A TOW TRUCK PICK UP THE CAR FROM THE MB DEALERSHIP AND TAKE IT TO ANOTHER SHOP WHERE THEY FOUND AN ENGINE AND PUT IT IN FOR A LITTLE LESS, I HAD TO HAVE IT DONE SINCE IT WAS LEASED AND I HAD TO RETURN IT BACK TO MB. I HOPE THAT MB TAKES RESPONSIBILITY FOR THIS. *TR
NHTSA ODI #10437329
67,000 miles · Oct 5, 2011
Engine And Engine CoolingPower Train
THE ENGINE LIGHT CAME ON ASKING ME TO GO TO THE NEXT GAS STATION AND CHECK OIL. WHEN I TOOK TO THE NEXT DAY TO A MECHANIC AND UPON A THOROUGH DIAGNOSTICS, I WAS TOLD THAT THE BALANCE SHAFT (IN TAKE CAMSHAFT CODE 1208) AND EXHAUST CAMSHAFT, CODE 1200 NEED TO BE REPLACED DUE TO PREMATURE WEAR AND FAULTY PARTS. *TR
NHTSA ODI #10428841
68,000 miles · Sep 19, 2011
Fuel System, Gasoline
STRONG RAW FUEL ODOR WAS NOTICED AFTER FILL UP ON MULTIPLE OCCASIONS. INVESTIGATION FOUND THAT BOTH THE FUEL PUMP HOUSING AND THE FUEL SENDER HOUSINGS WERE CRACKED ALLOWING RAW FUEL TO LEAK OUT. THIS IS EXACTLY THE SAME AS THE E CLASS RECALL. THIS RECALL NEEDS TO BE EXTENDED TO INCLUDE THE C CLASS AS WELL AS THIS CAR HAS AN I…
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STRONG RAW FUEL ODOR WAS NOTICED AFTER FILL UP ON MULTIPLE OCCASIONS. INVESTIGATION FOUND THAT BOTH THE FUEL PUMP HOUSING AND THE FUEL SENDER HOUSINGS WERE CRACKED ALLOWING RAW FUEL TO LEAK OUT. THIS IS EXACTLY THE SAME AS THE E CLASS RECALL. THIS RECALL NEEDS TO BE EXTENDED TO INCLUDE THE C CLASS AS WELL AS THIS CAR HAS AN IDENTICAL FAILURE MODE. *KB
NHTSA ODI #10426315
Official recalls
5Nov 19, 2024
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2001-2011 C-Class, CLK, E-Class, and CLS vehicles. Please see the recall report for a complete list of models and model years. The glass sunroof panel may not be properly secured and can detach.
Consequence & remedy
Consequence: A detached sunroof panel can become a road hazard, increasing the risk of a crash.
Remedy: Dealers will inspect and replace the sunroof panel as necessary, free of charge. Owner notification letters were mailed January 10, 2025. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of previous NHTSA recall number 22V-954. MBUSA's number for this recall is 2024120001/2/3.
Dec 23, 2022
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2001-2011 C-Class, CLK, E-Class, and CLS vehicles. Please refer to MBUSA's recall report for specific vehicle model details. The glass sunroof panel may not be properly secured and may detach.
Consequence & remedy
Consequence: A detached sunroof panel may become a road hazard, increasing the risk of a crash.
Remedy: Dealers will inspect and replace the sunroof panel as necessary free of charge. Owner notification letters were mailed February 3, 2023. Owners may contact MBUSA customer service at 1-800-367-6372. This recall expands NHTSA recall number 19V-918. MBUSA's numbers for this recall are 2023010004, 2023010005, and 2023010006.
Mar 19, 2021
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2006-2007 C350, C230, C280, CLK350, E320CDI, E350 Wagon, E350, 2006 C55 AMG, CLK500, CLS500, CLS55 AMG, E500 Wagon, E500, E55 AMG, 2007 CLK550, CLS550, CLS63 AMG, E550, E63 AMG, and E63 Wagon AMG vehicles. The bonding between the glass panel and the sliding roof frame may deteriorate, possibly causing the glass panel to detach from the vehicle.
Consequence & remedy
Consequence: A detached glass panel can separate from the vehicle and become a road hazard, increasing the risk of a crash.
Remedy: MBUSA will notify owners, and dealers will inspect the glass panel bonding and replace the sliding roof, as necessary, free of charge. Owner letters were mailed May 7, 2021. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of recall number 19V-918. MBUSA's number for this recall is 2021040012.
Dec 20, 2019
Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2001-2011 vehicles. The bonding between the glass panel and the sliding roof frame may deteriorate, possibly resulting in the glass panel detaching from the vehicle. For a full list of the affected models visit: https://static.nhtsa.gov/odi/rcl/2019/RMISC-19V918-4126.pdf
Consequence & remedy
Consequence: A detached glass panel can separate from the vehicle and become a road hazard, increasing the risk of a crash.
Remedy: MBUSA will notify owners, and dealers will inspect the glass panel bonding and replace the sliding roof, as necessary, free of charge. The recall began July 10, 2020. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2020040011.
Feb 11, 2016
Mercedes-Benz USA, LLC. (MBUSA) is recalling certain model year 2009-2010 ML320 BlueTec 4Matic, GL320 BlueTec 4Matic and R320 CDI 4Matic, 2011 E350 Cabriolet and E550 Cabriolet, 2009-2011 ML350, ML350 4Matic, ML550 4Matic, ML63 AMG, and C63 AMG, 2010-2011 ML450 4Matic Hybrid, E350 Coupe, E350 4Matic, E550 Coupe, E550 4Matic, and E63 AMG, 2011-2012 GL350 BlueTec 4Matic and R350 BlueTec 4Matic, 2009-2012 GL450 4Matic, GL550 4Matic and R350 4Matic, 2007-2008 SLK280, SLK350, and SLK55 AMG, 2011-2014 SLS AMG Coupe, 2012 SLS AMG Cabriolet, 2013-2014 SLS AMG GT and SLS AMG GT Cabriolet, 2005 C230 Kompressor and C320, 2006-2007 C230, 2006-2011 C350, 2008-2011 C300 and C300 4Matic, 2010-2012 GLK350 and GLK350 4Matic and 2007-2008 Chrysler Crossfire vehicles. Upon deployment of the driver's frontal air bag, excessive internal pressure may cause the inflator to rupture.
Consequence & remedy
Consequence: In the event of a crash necessitating deployment of the driver's frontal air bag, the inflator could rupture with metal fragments striking the driver or other occupants resulting in serious injury or death.
Remedy: MBUSA will their notify owners, and Fiat Chrysler will notify the affected Chrysler owners. Dealers for the respective brands will replace the driver's frontal air bag module, free of charge. This recall began November 2016. Mercedes-Benz owners may contact MBUSA customer service at 1-800-367-6372 and Chrysler owners may contact Fiat Chrysler customer service at 1-800-853-1403.
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.