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2018 Jeep Cherokee

Owner reports · Recalls · Investigations

More warning signs than most Cherokee years

Owner complaints for the 2018 Jeep Cherokee are substantially higher than the model-year median of 113.

About this comparison →

When problems were reported

Mileage at the reported incident

359 reports with mileage · 324 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.

  • Power Train. Review the 292 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Electrical System. Review the 190 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
  • Engine. Review the 155 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →

NHTSA owner reports · September 18, 2026 snapshot.

11 crash reports5 fire reports3 injury reports

What owners actually said

683 reports
Mileage unknown · Oct 16, 2023
Service Brakes

I see no open recalls on this issue however I did find a class action lawsuit related to this issue. My emergency (Parking) brake engaged and will not disengage. I stopped to get gas yesterday and upon re-entering the vehicle two lights appeared, the service parking brake message appeared on the screen along with the brake light…

Read full complaint

I see no open recalls on this issue however I did find a class action lawsuit related to this issue. My emergency (Parking) brake engaged and will not disengage. I stopped to get gas yesterday and upon re-entering the vehicle two lights appeared, the service parking brake message appeared on the screen along with the brake light. The car would not move the brakes would not disengage. Several attempts to press the switch to turn off the parking brake failed. I sat for 5 hours at a gas station waiting for AAA to find me a tow truck to get home. They were unable to locate a tow because of the need to dolly the vehicle because of the engaged parking brake. A friend came to assist me and after several thousand tries the parking brake disengaged. He followed me home (5 miles). This morning I attempted to take the car in for service as the warning lights were still on the dash. The parking brake is again on and will not disengage.

NHTSA ODI #11550153

Mileage unknown · Oct 2, 2023
Service Brakes

Water is leaking from body seems and shorting out parking module. It has happened twice.

NHTSA ODI #11547834

Mileage unknown · Sep 16, 2023
Electrical SystemEngine

Engine Failure 3 out of 4 cylinders not working 122,000 miles on car and regular service for oil changes and maintenance

NHTSA ODI #11544888

Mileage unknown · Sep 11, 2023
Electrical SystemSteeringVisibility/wiper

Turn into our street, windshield whippers came on. Fuse blown, take out still stay on. Kept changing them, Fuse kept blowning. Replace mod with turn single, wheel part. Pic sent. Worked two weeks, did it again. Now they are saying it's the radio is pulling to much, relay needs to be replace the radio. Which mileage, radio, back …

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Turn into our street, windshield whippers came on. Fuse blown, take out still stay on. Kept changing them, Fuse kept blowning. Replace mod with turn single, wheel part. Pic sent. Worked two weeks, did it again. Now they are saying it's the radio is pulling to much, relay needs to be replace the radio. Which mileage, radio, back up camera, whatever else is connected together causing the problem. This safety problem because back up could hit someone or something, whippers just coming on scared, hurting window, windshield whippers it self if dry out. This should be recall and concern. I don't understand why this not. Jow it's taken so long figure out problems at car place. They took the suv apart still cant figure problem out. Thank you [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI #11543975

Mileage unknown · Sep 6, 2023
Electrical SystemUnknown Or Other

I am getting random "service shifter" fault message displayed. No apparent fault or change when driving. Contacted Jeep dealership and am told this is very common issue with no long term fix. Fix the problem please.

NHTSA ODI #11543020

Mileage unknown · Aug 28, 2023
Service Brakes

On two different occasions I was stopped at a red light with my foot firmly on the brake, and the car all of a sudden started moving forward. This caused me to barely be able to stop before hitting another vehicle. My foot was still on the brake even though the car was moving forward.

NHTSA ODI #11541099

Mileage unknown · Aug 24, 2023
Power Train

Service 4WD light came on. Vehicle was diagnosed at dealership and they advised the PTU needs to be replaced. This poses a serious risk for injury.

NHTSA ODI #11540453

Mileage unknown · Aug 15, 2023
Forward Collision AvoidanceService Brakes

The right side emergency brake engauged on its own after stopping had to reset the emergency brake to move again

NHTSA ODI #11538786

80,000 miles · Aug 11, 2023
Power Train

The contact owns a 2018 Jeep Cherokee. The contact stated that while driving at an undisclosed speed, the vehicle lost PTU functionality. Additionally, the service footwell drive warning light was illuminated. The contact related the failure to NHTSA Campaign Number: 23V302000 (Power Train). The vehicle was taken to an independ…

Read full complaint

The contact owns a 2018 Jeep Cherokee. The contact stated that while driving at an undisclosed speed, the vehicle lost PTU functionality. Additionally, the service footwell drive warning light was illuminated. The contact related the failure to NHTSA Campaign Number: 23V302000 (Power Train). The vehicle was taken to an independent mechanic, who replaced the front drive shaft and the rear end of the vehicle; however, the failure persisted. The manufacturer was not made aware of the failure. The failure mileage was approximately 80,000.

NHTSA ODI #11537919

Mileage unknown · Aug 6, 2023
Power Train

The Service Shifter message comes on replacing the speedometer display on the dash. All of the LED's on the shifter bezel light up when it occurs, so you can't tell the gear you are in. It has been happening more frequently lately and began around 3 years ago. The only way to reset it is to put it in PARK and shut the car off …

Read full complaint

The Service Shifter message comes on replacing the speedometer display on the dash. All of the LED's on the shifter bezel light up when it occurs, so you can't tell the gear you are in. It has been happening more frequently lately and began around 3 years ago. The only way to reset it is to put it in PARK and shut the car off and restart it. I am on the Jeep Cherokee Club and see this quite often on their forums. It happens now every 2nd or 3rd time I drive it. Thanks.

NHTSA ODI #11536721

Official recalls

7

25V011000 · Power Train

Apr 29, 2025

Chrysler (FCA US, LLC) is recalling certain 2017-2019 Jeep Cherokee vehicles. The power transfer unit (PTU) may become damaged and disengage the transmission and differential, resulting in a loss of drive power and/or loss of park function.

Consequence & remedy

Consequence: A loss of drive power can increase the risk of a crash. A loss of park function can cause an unintended vehicle rollaway, which can increase the risk of a crash or injury.

Remedy: Dealers will update the drivetrain control module and PTU software and replace the PTU, as necessary free of charge. Owner notification letters were mailed beginning February 19, 2026. Owners may contact FCA customer service at 1-800-853-1403. FCA's number for this recall is 01C.

18V524000 · Electrical System:wiring:front Underhood

Aug 9, 2018

Chrysler (FCA US LLC) is recalling certain 2018 Jeep Renegade, Compass and Grand Cherokee, RAM 1500 and Promaster, Fiat 500x, Dodge Journey, Challenger, Charger and Durango and Chrysler 300x vehicles, 2017-2018 Jeep Wrangler, Dodge Grand Caravan and Chrysler Town and Country vehicles and 2018-2019 Jeep Cherokee and 2018 Chrysler Pacifica and Pacifica Hybrid vehicles. The powertrain control module may be equipped with a voltage regulator chip in the circuit board that may fail, causing a stall or a no start condition.

Consequence & remedy

Consequence: A vehicle stall can increase the risk of a crash.

Remedy: Chrysler will notify owners, and dealers will replace the powertrain control module, free of charge. The recall began October 2, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is U87.

18V494000 · Power Train:axle Assembly:axle Shaft

Jul 26, 2018

Chrysler (FCA US LLC) is recalling certain 2018 Jeep Cherokee all-wheel-drive vehicles. The bearing cage for the right front halfshaft assembly may not have been properly heat treated, possibly resulting in the bearing cage breaking and a potential halfshaft assembly failure.

Consequence & remedy

Consequence: If the halfshaft bearing cage breaks, the halfshaft may not be able to transmit engine power, causing a loss of drive or it can allow the vehicle to move while in the "Park" position. Either condition may increase the risk of a crash.

Remedy: Chrysler will notify owners, and dealers will replace the front right halfshaft assemblies, free of charge. The recall began September 20, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is U78.

18V332000 · Electrical System:software; Electrical System:wiring; Vehicle Speed Control:cruise Control

May 17, 2018

Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.

Consequence & remedy

Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.

Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.

Additional source detail variants (3)

Electrical System:software

Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.

Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.

Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.

Vehicle Speed Control:cruise Control

Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.

Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.

Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.

Electrical System:wiring

Chrysler (FCA US LLC) is recalling certain 2014-2018 Dodge Journey, Charger and Durango, RAM 2500, 3500, 3500 Cab Chassis (more than 10,000lb), 4500 Cab Chassis and 5500 Cab Chassis, Jeep Cherokee and Grand Cherokee and Chrysler 300, 2014-2019 RAM 1500, 2015-2018 Dodge Challenger, 2015-2017 Chrysler 200, 2016-2018 RAM 3500 Cab Chassis (less than 10,000 lb), 2017-2018 Chrysler Pacifica and 2018 Jeep Wrangler vehicles. These vehicles are being recalled to address a defect that could prevent the cruise control system from disengaging. If, when using cruise control, there is a short circuit within the vehicle's wiring, the driver may not be able to shut off the cruise control either by depressing the brake pedal or manually turning the system off once it has been engaged, resulting in either the vehicle maintaining its current speed or possibly accelerating.

Consequence: If the vehicle maintains its speed or accelerates despite attempts to deactivate the cruise control, there would be an increased risk of a crash.

Remedy: Chrysler will notify owners, and dealers will inspect the software, and perform a software flash on the engine or powertrain control module, free of charge. The recall began June 4, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Note: Owners are advised to stop using cruise control until the software update has been performed. In the event that cruise control cannot be disengaged while driving, owners should firmly and steadily apply the brakes and shift the transmission to neutral, placing the vehicle in park once it has stopped.

18V282000 · Fuel System, Gasoline:delivery:hoses, Lines/piping, And Fittings

May 1, 2018

Chrysler (FCA US LLC) is recalling certain 2018 Jeep Cherokee vehicles equipped with a 2.4L engine. These vehicles may have been manufactured with a fuel tube that may leak fuel into the engine compartment.

Consequence & remedy

Consequence: A fuel leak in the presence of the ignition source can increase the risk of a fire.

Remedy: Chrysler will notify owners, and dealers will inspect the fuel tube, replacing it as necessary, free of charge. The recall began May 24, 2018. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is U39.

17V670000 · Engine And Engine Cooling:engine

Oct 24, 2017

Chrysler (FCA US LLC) is recalling certain 2018 Jeep Cherokee and Compass vehicles equipped with 2.4L engines. The engines may have a cracked oil pump housing that can result in oil pump failure.

Consequence & remedy

Consequence: If the oil pump fails, the engine will stall, increasing the risk of a crash.

Remedy: Chrysler will notify owners, and dealers will inspect the oil pump, replacing it as necessary, free of charge. The recall began December 5, 2017. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is T65.

17V543000 · Equipment:other:labels; Wheels:rim

Aug 31, 2017

Chrysler (FCA US LLC) is recalling certain 2017-2018 Jeep Cherokee vehicles. The tire and rim size information required to be on the Certification label was omitted during manufacturing, which may result in an incorrect tire and rim combination being installed on the vehicle. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 110, "Tire Selection and Rims."

Consequence & remedy

Consequence: The missing tire and rim designation information may lead to an incorrect combination being installed on the vehicle, increasing the risk of a crash.

Remedy: Chrysler will notify owners and will provide a corrected certification label, free of charge. The recall began October 13, 2017. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is T53.

Additional source detail variants (2)

Equipment:other:labels

Chrysler (FCA US LLC) is recalling certain 2017-2018 Jeep Cherokee vehicles. The tire and rim size information required to be on the Certification label was omitted during manufacturing, which may result in an incorrect tire and rim combination being installed on the vehicle. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 110, "Tire Selection and Rims."

Consequence: The missing tire and rim designation information may lead to an incorrect combination being installed on the vehicle, increasing the risk of a crash.

Remedy: Chrysler will notify owners and will provide a corrected certification label, free of charge. The recall began October 13, 2017. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is T53.

Wheels:rim

Chrysler (FCA US LLC) is recalling certain 2017-2018 Jeep Cherokee vehicles. The tire and rim size information required to be on the Certification label was omitted during manufacturing, which may result in an incorrect tire and rim combination being installed on the vehicle. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 110, "Tire Selection and Rims."

Consequence: The missing tire and rim designation information may lead to an incorrect combination being installed on the vehicle, increasing the risk of a crash.

Remedy: Chrysler will notify owners and will provide a corrected certification label, free of charge. The recall began October 13, 2017. Owners may contact Chrysler customer service at 1-800-853-1403. Chrysler's number for this recall is T53.

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.