NHTSA owner reports · September 18, 2026 snapshot.
Fuel/propulsion System complaints
53 reportsClear category filter66,000 miles · Jul 30, 2018
EngineFuel/propulsion SystemPower Train
I'VE BROUGHT MY 2013 CHEVY VOLT TO THE DEALERSHIP 4 TIMES BECAUSE IT DIES SUDDENLY WHILE DRIVING. IT HAS PUT MY FAMILY IN DANGER MULTIPLE TIMES. ONE OF THE "FIXES" WAS A SOFTWARE UPDATE THAT ENDED UP AS A RECALL BECAUSE IT CAUSES THE ENGINE TO DIE SUDDENLY (IT'S RECALL #N172130460, WHICH CAME OUT TWO DAYS BEFORE MY LATEST INCIDE…
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I'VE BROUGHT MY 2013 CHEVY VOLT TO THE DEALERSHIP 4 TIMES BECAUSE IT DIES SUDDENLY WHILE DRIVING. IT HAS PUT MY FAMILY IN DANGER MULTIPLE TIMES. ONE OF THE "FIXES" WAS A SOFTWARE UPDATE THAT ENDED UP AS A RECALL BECAUSE IT CAUSES THE ENGINE TO DIE SUDDENLY (IT'S RECALL #N172130460, WHICH CAME OUT TWO DAYS BEFORE MY LATEST INCIDENT, BUT I DIDN'T RECEIVE THE RECALL NOTICE IN THE MAIL UNTIL 7/28/18...6 WEEKS AFTER MY LAST INCIDENT). THE MOST RECENT TIME THE CAR DIED (6/16/18), I WAS ON A MOUNTAIN HIGHWAY AND I WAS LUCKY ENOUGH TO NOT GET HIT AS I PULLED THE CAR TO THE SIDE. THERE WAS NO SIGNAGE THERE EXCEPT FOR THE "CAUTION BEAR XING" SIGN. AFTER TOWING MY CAR TO THE NEAREST DEALERSHIP (IN CARSON CITY, NV, AN 8 HOUR ORDEAL), I HAD EXPENSES FOR LODGING AND TRANSPORTATION (INCLUDING LYFT TO SOUTH LAKE TAHOE TO RENT A CAR BECAUSE NO RENTAL CAR OFFICES OPEN ON SUNDAY IN CARSON CITY, THEN FLYING TO RENO AND TAKING A LYFT TO CARSON CITY TO PICK UP THE CAR BECAUSE CHEVY REFUSED TO SHIP THE CAR TO ME EVEN THOUGH I SAID THAT I WAS AFRAID AND DIDN'T TRUST THE CAR IN THE MOUNTAINS). CHEVY CUSTOMER SERVICE AND CONCIERGE SERVICES REFUSED TO REIMBURSE ME BECAUSE I HAD THE CAR TOWED MYSELF INSTEAD OF CALLING THEIR "CONCIERGE SERVICE" TO TOW IT BECAUSE THAT'S "POLICY." HOW ABOUT THE SAFETY OF THEIR CUSTOMERS SO THAT THEY MAY LIVE TO DRIVE ANOTHER DAY? I'M NOT ASKING FOR ANYTHING MORE THAN THE EXPENSES INCURRED FROM THE LAST ADVENTURE: $1040.72, WHICH I CAN ITEMIZE. OTHER TIMES THAT MY CAR HAS DIED INCLUDE: WHILE MAKING A U-TURN IN A BUSY INTERSECTION (IN 2016), IT DIED AND STARTED BACK UP AS IF NOTHING HAPPENED 20 MINUTES LATER AND A SEPARATE TIME WAS WHEN THE CAR WOULDN'T START AT ALL BUT THEN STARTED UP AGAIN TWO HOURS LATER AS IF THERE WAS NEVER AN ISSUE.EVERY TIME THIS HAPPENED, I HAD A "POWER PROPULSION REDUCED" WARNING ON MY DASHBOARD. I SEE ONLINE THAT MANY HAVE HAD THIS ISSUE.
NHTSA ODI #11114664
35,063 miles · Apr 27, 2017
Fuel/propulsion System
DRIVING IN TRAFFIC, MULTIPLE LANES.." REDUCED POWER" MESSAGE APPEARS ON DASH..CAR SHUTS DOWN IMMEDIATELY...NO STEERING ASSIST...BRAKES OKAY...STUCK IN MIDDLE LANES WITH NO PROPULSION...LUCKILY A FIRETRUCK HAPPENED BY AND WAS PUSHED OFF THE ROAD...CAR TOWED TO DEALER. INFORMED MULTIPLE VOLTS TOWED IN FOR SAME ISSUE. ALSO INFORM…
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DRIVING IN TRAFFIC, MULTIPLE LANES.." REDUCED POWER" MESSAGE APPEARS ON DASH..CAR SHUTS DOWN IMMEDIATELY...NO STEERING ASSIST...BRAKES OKAY...STUCK IN MIDDLE LANES WITH NO PROPULSION...LUCKILY A FIRETRUCK HAPPENED BY AND WAS PUSHED OFF THE ROAD...CAR TOWED TO DEALER. INFORMED MULTIPLE VOLTS TOWED IN FOR SAME ISSUE. ALSO INFORMED EXTREME BACKORDER FOR REPAIR BATTERY ACROSS U. S. TOLD APPROX 2 MONTH WAIT FOR BATTERY SECTION...ONCE THIS BATTERY FAILS WHILE YOU ARE DRIVING, YOU ARE DEAD IN THE WATER...NO POWER STEERING AND UNABLE TO MOVE IN OR OUT OF TRAFFIC...IF THIS DEALER HAS 3 CARS, HOW MANY UNSAFE CARS ARE THERE ACROSS THE COUNTRY?
NHTSA ODI #10981172
34,000 miles · Apr 6, 2017
Fuel/propulsion System
LOST POWER WHILE DRIVING DOWN THE ROAD!
NHTSA ODI #10970845
30,000 miles · Sep 6, 2016
Fuel/propulsion SystemFire
TL* THE CONTACT OWNS A 2013 CHEVROLET VOLT. WHILE DRIVING FOR MORE THAN TWO HOURS OVER 75 MPH, THE "PROPULSION POWER LOW DECREASE SPEED" MESSAGE DISPLAYED AND THE SPEED DECREASED TO 55 MPH. WHEN THE FAILURE OCCURRED, SMOKE WAS PRESENT INSIDE AND OUTSIDE THE VEHICLE AND THE ODOR OF FUEL WAS PRESENT. THE CONTACT INDICATED THAT THE…
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TL* THE CONTACT OWNS A 2013 CHEVROLET VOLT. WHILE DRIVING FOR MORE THAN TWO HOURS OVER 75 MPH, THE "PROPULSION POWER LOW DECREASE SPEED" MESSAGE DISPLAYED AND THE SPEED DECREASED TO 55 MPH. WHEN THE FAILURE OCCURRED, SMOKE WAS PRESENT INSIDE AND OUTSIDE THE VEHICLE AND THE ODOR OF FUEL WAS PRESENT. THE CONTACT INDICATED THAT THE FAILURE OCCURRED ON MULTIPLE OCCASIONS. THE CAUSE OF THE FAILURE WAS NOT DIAGNOSED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 30,000.
NHTSA ODI #10903872
32,800 miles · Mar 24, 2016
EngineFuel/propulsion SystemPower Train
WHILE DRIVING DOWN A ROAD IN INDIANAPOLIS AT 35 MILES PER HOUR, MY CAR SUDDENLY SLOWED DOWN AND A MESSAGE READING " ENGINE NOT AVAILABLE - SERVICE SOON" APPEARED ON MY HUD. MY CAR ONLY HAS 32,800 MILES ON IT AND A CLEAN TITLE. NOTHING ABOUT MY DRIVING CHANGED TO CAUSE THIS ISSUE, IT WAS SUDDEN AND WITHOUT APPARENT CAUSE. I HAD T…
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WHILE DRIVING DOWN A ROAD IN INDIANAPOLIS AT 35 MILES PER HOUR, MY CAR SUDDENLY SLOWED DOWN AND A MESSAGE READING " ENGINE NOT AVAILABLE - SERVICE SOON" APPEARED ON MY HUD. MY CAR ONLY HAS 32,800 MILES ON IT AND A CLEAN TITLE. NOTHING ABOUT MY DRIVING CHANGED TO CAUSE THIS ISSUE, IT WAS SUDDEN AND WITHOUT APPARENT CAUSE. I HAD THE CAR TAKEN TO THE MECHANIC, AND GM JUST RESET THE CODES. IT IS DRIVING OK FOR NOW, BUT A RESET OF CODES IS A TEMPORARY FIX TO THE ISSUE, AND I'VE READ EXTENSIVELY ABOUT MANY, MANY OTHER VOLT OWNERS WITH THE SAME ISSUE. IT IS EXTREMELY DANGEROUS TO HAVE YOUR ENGINE SHUT OFF WHILE DRIVING, ESPECIALLY IF I HAD BEEN ON THE HIGH WAY DURING RUSH HOUR. THIS IS SOMETHING THAT NEEDS LOOKED INTO, AND I FEEL THAT GM IS TRYING TO BURY IT WITH RESETS WHICH AREN'T WORKING FOR MOST PEOPLE.
NHTSA ODI #10851456
Mileage unknown · Sep 18, 2015
EngineFuel/propulsion SystemPower TrainCrashInjury
WHILE ENTERING IN THE HIGHWAY THE CAR STARTED TO DECELERATE REGARDLESS THE FACT THE GAS PEDAL WAS PUSHED SEVERAL TIMES. THE CAR DECELERATED AND THEN STALLED. THE CAR HAS BEEN REAR ENDED BY THE CAR BEHIND. THIS COULD HAVE BEEN A MUCH MORE SERIOUS ACCIDENT AND IT WAS A VEHICLE FAILURE.
NHTSA ODI #10765090
17,400 miles · Apr 14, 2015
EngineFuel/propulsion SystemPower Train
A WARNING MESSAGE APPEARED ON THE DASH, WHICH SAID "PROPULSION POWER IS REDUCED," FOLLOWED BY, "ENGINE NOT AVAILABLE. SERVICE SOON," AS WELL AS A CHECK ENGINE LIGHT. I PRESSED THE ONSTAR BUTTON TO FIND OUT WHAT WAS WRONG BUT THEY HAD NEVER HEARD OF THE ERROR MESSAGE AND COULD NOT ESTABLISH COMMUNICATION WITH THE VEHICLE TO PERFO…
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A WARNING MESSAGE APPEARED ON THE DASH, WHICH SAID "PROPULSION POWER IS REDUCED," FOLLOWED BY, "ENGINE NOT AVAILABLE. SERVICE SOON," AS WELL AS A CHECK ENGINE LIGHT. I PRESSED THE ONSTAR BUTTON TO FIND OUT WHAT WAS WRONG BUT THEY HAD NEVER HEARD OF THE ERROR MESSAGE AND COULD NOT ESTABLISH COMMUNICATION WITH THE VEHICLE TO PERFORM DIAGNOSTICS. WHILE ON HOLD WITH ONSTAR, THE VEHICLE BEGAN TO SPONTANEOUSLY DECELERATE VERY RAPIDLY DESPITE MY ATTEMPTS TO ACCELERATE, IN THE MIDDLE OF FAST HIGHWAY TRAFFIC. I MADE IT OVER TO THE SIDE OF THE ROAD SAFELY, LIMPING ALONG AT 3-10 MPH, WITH THE HELP OF A GOOD SAMARITAN WHO BLOCKED TRAFFIC FOR ME. THIS IS A SPONTANEOUS OCCURRENCE, WITH NO MAINTENANCE NEGLIGENCE TO EXPLAIN THE EVENT. THE CAR WAS TOWED TO A DEALER, WHICH HAS YET TO DETERMINE THE SOURCE OF THE ISSUE. *TR
NHTSA ODI #10705646
15,000 miles · Nov 18, 2014
Fuel/propulsion System
THE INCIDENT OCCURRED ON 8/27/14, AND RESULTED IN MY WIFE ME TAKEN TO THE HOSPITAL AND TREATED FOR CARBON MONOXIDE POISONING. THE INCIDENT OCCURRED AT OUR HOME. THE VOLT WAS PARKED IN THE ENCLOSED GARAGE ON 8/26 AROUND 7PM. THE 240 VOLT CHARGER WAS PLUGGED IN AS USUAL. I DID NOT NOTICE ANYTHING UNUSUAL AFTER PLUGGING IN THE …
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THE INCIDENT OCCURRED ON 8/27/14, AND RESULTED IN MY WIFE ME TAKEN TO THE HOSPITAL AND TREATED FOR CARBON MONOXIDE POISONING. THE INCIDENT OCCURRED AT OUR HOME. THE VOLT WAS PARKED IN THE ENCLOSED GARAGE ON 8/26 AROUND 7PM. THE 240 VOLT CHARGER WAS PLUGGED IN AS USUAL. I DID NOT NOTICE ANYTHING UNUSUAL AFTER PLUGGING IN THE CHARGER, AND THE VOLT WAS LEFT UNATTENDED UNTIL THE EMS ARRIVED AROUND 11AM THE FOLLOWING DAY. THE EMS PERSONNEL FOUND THE ENGINE RUNNING, VERY HIGH LEVELS OF CO UPON ENTERING THE GARAGE AND EVEN HIGHER LEVELS INSIDE THE CAR. THE INSIDE OF THE PASSAGE COMPARTMENT WAS DESCRIBED AS HOT. THE FRONT EXTERIOR OF THE CAR WAS TO HOT TO TOUCH AND THE CAR REAR WARM. THE TEMPERATURE UNDER THE CAR HOOD WAS DESCRIBED AS "RED HOT". THE ENGINE HAD CONSUMED AROUND 5 GALLONS OF GAS DURING THIS TIME PERIOD. DISTRIBUTION OF THE CO THROUGHOUT THE HOUSE WAS PROBABLY CAUSED BY THE A/C AIR HANDLER WHICH IS LOCATED INSIDE THE GARAGE. DATA DUMPS REVEALED POWER AND STARTING BATTERIES WERE EXHAUSTED, AND NO FAULT FLAGS DROPPED. I BELIEVE THE INCIDENT HAS REVEALED: -THE TEMPERATURE LEVELS REACHED UNDER THE HOOD PROBABLY EXCEEDED THE SAFE OPERATING LEVELS OF THE DIGITAL SYSTEMS SOLID STATE JUNCTIONS RENDERING ANY DATA COLLECTED (OR NOT COLLECTED) AS UNRELIABLE. -THE LITHIUM ION AND STARTING BATTERIES WERE TOTALLY W/O CHARGE. HOW CAN THIS HAPPEN WHEN THE SOLE FUNCTION OF THE GAS ENGINE ( WHICH WAS RUNNING WHEN DISCOVERED BY THE FIREMEN ) IS TO CHARGE THESE BATTERIES UNLESS A FAILURE OCCURRED. NOTE: ALL PERSONAL INFO STORED IN THE CAR ENTERTAINMENT HARD DRIVE SYSTEM WAS LOST. -HOW CAN THE CAR OUTSIDE SURFACE GET THAT HOT? ONE POSSIBILITY IS THE BODY IS TEMPORARILY USED AS A RETURN GROUND PASSING VERY HIGH LEVELS OF CURRENT BECAUSE OF A FAILURE. *TR
NHTSA ODI #10658921
6,600 miles · Oct 14, 2014
Electrical SystemEngineFuel/propulsion System
I RECEIVED THE FOLLOWING MESSAGE ON THE CAR DASH DISPLAY: PROPULSION REDUCED-ENGINE NOT AVAILABLE. THIS MESSAGE CAME ON WHILE I WAS DRIVING IN THE CARPOOL LANE. I CALLED GM THRU ON STAR AND WAS TOLD THAT I HAD A CATASTROPHIC ERROR AND NEEDED TO GET MY CAR INTO REPAIR WITH 24 HOURS. WITH ONLY 6 MILES LEFT ON THE BATTERY, I TO…
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I RECEIVED THE FOLLOWING MESSAGE ON THE CAR DASH DISPLAY: PROPULSION REDUCED-ENGINE NOT AVAILABLE. THIS MESSAGE CAME ON WHILE I WAS DRIVING IN THE CARPOOL LANE. I CALLED GM THRU ON STAR AND WAS TOLD THAT I HAD A CATASTROPHIC ERROR AND NEEDED TO GET MY CAR INTO REPAIR WITH 24 HOURS. WITH ONLY 6 MILES LEFT ON THE BATTERY, I TOLD THE GM REP THAT I BETTER GET THE CAR TO A CHEVY DEALER. I IMMEDIATELY DROVE TO THE DEALERSHIP IN CULVER CITY. THE MINUTE I PULLED INTO THE DRIVEWAY OF THE DEALERSHIP, MY CAR STOPPED AND WOULD NOT RESTART. THIS COULD HAVE BEEN A DISASTER IF THE CAR HAD STOPPED IN THE CARPOOL LANE. I HAVE READ OF OTHER COMPLAINTS ON GOOGLE AND YAHOO. I WAS TOLD BY THE DEALERSHIP THAT THEY WERE GOING TO REPLACE THE ENGINE MODULE, WHICH THEY SAID WOULD TAKE 8 HOURS TO REPAIR, BUT WHEN I PICKED UP THE CAR, THEY ONLY REPLACED THE TRANSMISSION MODULE. SINCE THE INCIDENT, I ONLY GET A FULL CHARGE OF 32 TO 34 MILES, WHERE BEFORE THE INCIDENT I WAS GETTING A FULL CHARGE OF 42 TO 44 MILES PER CHARGE. THIS IS DEFINITE SAFETY ISSUE AS GM BLAMES THE DRIVER FOR THE PROBLEM. GM NEEDS TO REPLACE THE ENGINE MODULE ON MY CAR. *TR
NHTSA ODI #10644626
11,669 miles · May 8, 2014
Electrical SystemEngineFuel/propulsion System
THE VEHICLE HAS REPEATEDLY SHUT DOWN WHILE DRIVING/FAILED TO START SINCE JUNE 2013. THE VEHICLE HAS BEEN IN SERVICE DUE TO REPAIRS = 42 DAYS IN THE LAST 10 MONTHS. GM CONTINUES TO REPLACE/RECALL PARTS ON THE HYBRID BATTERY AS WELL AS OTHER PARTS CONCERNING SECONDARY PROBLEMS. I AM AFRAID THIS VEHICLE WILL SHUT DOWN AGAIN WHIL…
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THE VEHICLE HAS REPEATEDLY SHUT DOWN WHILE DRIVING/FAILED TO START SINCE JUNE 2013. THE VEHICLE HAS BEEN IN SERVICE DUE TO REPAIRS = 42 DAYS IN THE LAST 10 MONTHS. GM CONTINUES TO REPLACE/RECALL PARTS ON THE HYBRID BATTERY AS WELL AS OTHER PARTS CONCERNING SECONDARY PROBLEMS. I AM AFRAID THIS VEHICLE WILL SHUT DOWN AGAIN WHILE I AM DRIVING CAUSING AN ACCIDENT HURTING ME OR OTHERS ON THE ROAD. CLEARLY, IT IS A POTENTIAL DEATH TRAP. *TR
NHTSA ODI #10587172
Official recalls
3Jul 27, 2023
General Motors, LLC (GM) is recalling certain 2013 Buick Verano, Chevrolet Camero, Sonic, and Volt vehicles. The driver-side 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, resulting in serious injury or death.
Remedy: Dealers will replace the driver-side air bag module, free of charge. On some 2013 Volt vehicles, the steering wheel will be replaced as well, free of charge. Owner notification letters were mailed October 23, 2023. Owners may contact Buick customer service at 1-800-521-7300 and Chevrolet customer service at 1-800-222-1020. GM's number for this recall is N232413120.
Jun 14, 2018
General Motors LLC (GM) is recalling certain 2013 Chevrolet Volt vehicles. An update to the Hybrid Powertrain Control Module 2 (HPCM2) may have disabled the cell balancing function causing a low-voltage condition.
Consequence & remedy
Consequence: If the voltage drops, the vehicle may lose propulsion, increasing the risk of crash.
Remedy: GM will notify owners, and dealers will reprogram the HPCM2, free of charge. The recall began July 24, 2018. Owners may contact Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 18215.
Mar 13, 2015
General Motors LLC (GM) is recalling certain model year 2011-2013 Volt vehicles manufactured August 25, 2010, to June 26, 2013. If the driver exits the vehicle without turning off the electrical system, the battery may drain low enough that the gasoline engine will automatically start itself to recharge the electric battery.
Consequence & remedy
Consequence: If the engine runs for an extended period of time in an enclosed space, there may be a build up of carbon monoxide, increasing the risk of personal injury.
Remedy: GM will notify owners, and dealers will update the engine management software to limit the time that the stationary vehicle can be left in the ON position, free of charge. The recall began April 15, 2015. Owners may contact Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 14617.
Additional source detail variants (2)
Electrical System:ignition
General Motors LLC (GM) is recalling certain model year 2011-2013 Volt vehicles manufactured August 25, 2010, to June 26, 2013. If the driver exits the vehicle without turning off the electrical system, the battery may drain low enough that the gasoline engine will automatically start itself to recharge the electric battery.
Consequence: If the engine runs for an extended period of time in an enclosed space, there may be a build up of carbon monoxide, increasing the risk of personal injury.
Remedy: GM will notify owners, and dealers will update the engine management software to limit the time that the stationary vehicle can be left in the ON position, free of charge. The recall began April 15, 2015. Owners may contact Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 14617.
Engine And Engine Cooling:engine:gasoline
General Motors LLC (GM) is recalling certain model year 2011-2013 Volt vehicles manufactured August 25, 2010, to June 26, 2013. If the driver exits the vehicle without turning off the electrical system, the battery may drain low enough that the gasoline engine will automatically start itself to recharge the electric battery.
Consequence: If the engine runs for an extended period of time in an enclosed space, there may be a build up of carbon monoxide, increasing the risk of personal injury.
Remedy: GM will notify owners, and dealers will update the engine management software to limit the time that the stationary vehicle can be left in the ON position, free of charge. The recall began April 15, 2015. Owners may contact Chevrolet customer service at 1-800-222-1020. GM's number for this recall is 14617.
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
2DP22005 · Pedestrian Alert Sounds
Opened Jan 27, 2023 · Closed Aug 7, 2023
Status: closed (inferred from source dates) · Electrical System:propulsion System
NHTSA received a petition on or about July 18, 2022, requesting that Federal Motor Vehicle Safety Standard (FMVSS) 141 be applied to all electric and hybrid vehicles operating in the United States. The petition can be reviewed at NHTSA.gov under ODI Number 11486072. FMVSS 141 establishes performance requirements for pedestrian alert sounds for motor vehicles. The standard applies to hybrid and electric vehicles that have a gross vehicle weight rating of 4,536 KG or less or are defined as low-speed vehicles. The standard became fully applicable to all such vehicles manufactured on or after March 1, 2021.On January 27, 2023, NHTSA opened Defect Petition (DP) 22-005 to evaluate the subject matter described in the petition. On June 24, 2023 and as supplemented on June 25, 2023, the petitioner notified NHTSA he was withdrawing his petition. The petitioner indicated that, based on his review of data, there is no justification for asserting potential benefits that could be derived from actions sought by my petition. Based on the petitioner's withdrawal, DP22-005 is closed. Closure of this DP does not represent a determination by NHTSA regarding the subject matter of the petition.
PE19013 · Passenger Sensing System
Opened Sep 17, 2019 · Closed Jul 2, 2021
Status: closed (inferred from source dates) · Air Bags:sensor:occupant Classification:front Passenger
In September 2019, the Office of Defects Investigation (ODI) opened PE19-013 to assess the potential safety related effects of a malfunction of the Passenger Sensing System (PSS) in 2012-2013 Model Year (MY) Chevrolet Volt vehicles. Consumers reported that due to a malfunction of the PSS, the air bag system malfunction indicator light (MIL) was activated. Many of the complaints noted the malfunction occurred after the warranty period expired and mentioned high repair costs as a major deterrent to the repair of the vehicle.The PSS sensor mat is embedded in the front passenger seat cushion and is intended to detect child seats and small statured occupants who could be harmed by deployment of the frontal passenger air bag. The PSS may develop a malfunction due to bunching of the sensor mat in the seat trench. The bunching of the sensor mat could cause the mat to repeatedly fold in the same location. Over time, the repeated folding can cause an increased resistance in the sensor mat. An increased resistance in the PSS sensor mat is detected as a fault in the air bag system diagnostic. If this fault is detected, a diagnostic trouble code will be stored in the air bag control unit and the air bag MIL will illuminate.Further, if the fault is detected, the passenger frontal and knee air bags will be suppressed in a crash of sufficient severity to warrant a commanded deployment regardless of the nature of size of the occupant of the front passenger seat.The report counts shown above include only those reports that specifically address the issue covered by this investigation, failure of the PSS sensor mat. Reports alleging only that the air bag light is on with no cause stated, or where a different cause was otherwise identified, were excluded as the air bag light could be illuminated for system faults other than a PSS malfunction.The subject vehicles have been in service for approximately ten (10) years. An analysis of General Motors (GM) warranty data for the subject vehicles, including a comparison with other agency and manufacturer data pertaining to similar occupant detection system failure investigations, indicates the subject vehicles experience a comparatively low complaint rate for this issue given the number of years the vehicles have been in service.GM has instituted a cost reduction program for the repair/replacement of the PSS in the subject vehicles. Based on this cost reduction program as well as:1) a comparatively low warranty rate; 2) no reported injuries, deaths or asymmetric deployments; and 3) the age of the vehicles; ODI is closing this Preliminary Evaluation. The closing of this investigation does not constitute a finding by NHTSA that a safety related defect does not exist. The agency reserves the right to take additional action if warranted by new circumstances.The ODI complaints cited above can be viewed at www.nhtsa.gov under the following ODI identification numbers in a separate attachment.