2012 Toyota Prius Problems

Brake lights icons stay on mechanic at Toyota dealership state need new brak master cylinder and booster

Brake warning lights on, buzzing sound every 10 seconds. Likely a known actuator and master cylinder issue

Odometer Fraud. The contact purchased a 2012 Toyota Prius. The contact stated that while attempting to register the vehicle, it was discovered that there was a mileage discrepancy. The vehicle was a dealer sale. At the time of purchase, the vehicle mileage was 187,000, and at the time of registration, it was discovered that the mileage was 227,000.

While driving, the vehicle experienced a sudden brake system malfunction without prior warning or gradual degradation. The vehicle was being operated under normal driving, road, and weather conditions. No recent brake service, repairs, or aftermarket modifications had been performed prior to the failure. Multiple warning lights illuminated on the dashboard, including the ABS warning light, brake warning light, and traction control warning light. Shortly after the warning lights appeared, the vehicle began emitting continuous warning beeps. Audible buzzing or pumping noises were also present from the brake system during the malfunction. During this event, brake performance was reduced and braking felt inconsistent. The brake pedal became hard at times and spongy at other times, requiring increased effort to slow the vehicle and resulting in unpredictable braking response. This created a safety concern while the vehicle was in motion. The driver was forced to alter driving behavior and exercise extreme caution due to reduced braking confidence and unpredictable pedal feel. The malfunction has occurred intermittently during normal driving. The condition temporarily resolves on its own and later reoccurs without corrective action. The suspected failed component is the brake actuator / ABS actuator assembly. A diagnostic scan retrieved fault codes C1252 (Brake Booster Pump Motor ON Time Abnormally Long), C1253 (Pump Motor Relay Malfunction), and C1256 (Accumulator Low Pressure), which are consistent with brake actuator malfunction. The failure occurred at approximately 154,000 miles. This vehicle model and generation have a documented history of premature brake actuator failures with similar safety-related symptoms reported by other owners. The condition places the driver and others at risk due to unpredictable braking behavior, reduced braking effectiveness, and repeated warning alarms while driving. Warning lamps and audible alerts continue intermittently.

Brake master control system failure with constant issues over 80k miles. Forward running lights control housing has not held a light fixture since day one and dealership wants to charge for light replacement. It’s a faulty part and burnt through the housing. Olathe Toyota refused to repair under warranty saying it was a customer issue but is clearly a safety problem. Irresponsible dealer management.

The contact owns a 2012 Toyota Prius. The contact stated that the passenger's side low-beam headlight failed to provide adequate illumination while driving. The vehicle was taken to the dealer who informed the contact that no issues were found; however, the dealer replaced the headlight bulb. The contact stated that the headlight bulb was replaced several times; however, the failure persisted. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 100,000.

Unknown. There were a multitude of codes that appeared on the diagnostics causing problems with engine. The temperature, brake, tire sensor lights are all on. The cruise control is not working. White smoke emitting from tail pipe and engine. Main engine coolant leaking. Car overheating rapidly.

The contact owns a 2012 Toyota Prius. The contact stated that when the vehicle was started, there was a rattling sound coming from the vehicle. The contact stated that while depressing the accelerator pedal, the vehicle started shaking abnormally with a rattling sound. The vehicle was taken to the dealer where it was diagnosed with a blown head gasket and that the engine block needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 106,000.

There is no incident occurring to me .but I change some parts like head light.& whisper .engine .

The glass sunroof spontaneously exploded or imploded. There was a loud popping sound and I looked up at the sunroof, and it was shattered. glass started falling on me as I was driving on the highway. There have been many reported cases of this happening found online. https://topclassactions.com/lawsuit-settlements/lawsuit-news/toyota-owners-should-be-aware-of-reported-exploding-sunroof-risk/ It has not been inspected yet. no warning messages.

The front and driver side air bags did not deploy (although the passenger side air bag did deploy). Initial impact came from behind, toward the passenger side, causing the vehicle to turn fully sideways, where the vehicle was then t-boned on the driver's side. The lack of driver side air bag deployment resulted in a lot of glass making it into the left side of the driver's head.

The contact owns a 2012 Toyota Prius. The contact stated while attempting to use the horn, the horn failed to operate as needed. The contact also stated that the front passenger’s air bag warning light illuminated and then turned off. The vehicle was taken to the dealer to be diagnosed. The contact was informed that the clock spring failed and needed to be replaced. The vehicle was also taken to an independent mechanic who confirmed the cause of the failure. The vehicle was not repaired. The manufacturer informed the contact that the vehicle was not included in the manufacturer communications regarding the clock spring assembly repair. The vehicle was not repaired. The approximate failure mileage was 90,000.

Unknown. There were a multitude of codes that appeared on the diagnostics causing problems with engine. The temperature, brake, tire sensor lights are all on. The cruise control is not working. White smoke emitting from tail pipe and engine. Main engine coolant leaking. Car overheating rapidly.

Brake getting stuck on the floor would have to press on brake really hard just to get a response, this will happen out of the blue! Driving in highway or just driving off the driveway. I almost hit a car in front of me due to lack of brake, i had to swerve to the side! First appear 1 day after buying the car..This issue needs to be worked on right away.

Weather stripping around the solar sunroof cracked and has come off in sections. This is a very common problem with this specific model, but remains low due to the low numbers the solar sunroof packages was produced. Afraid the sunroof will leak if used, so it stays inoperable in order to not damage broken seals.

VEHICLE IS MANUFACTURED WITHOUT ANY REGARD FOR PREVENTING MICE FROM ENTERING THE PASSENGER INTERIOR--- AIR INTAKE VENT UNDER WINDSHIELD AND 2 REAR DECOMPRESSION VENTS LOCATED IN THE REAR CARGO COMPARTMENT ABOVE THE WHEEL WELLS ARE OPEN TO THE EXTERIOR ALLOWING UNIMPEDED ACCESS TO THE INTERIOR OF THE CAR. HAD MICE IN THIS CAR 2 WEEKS AFTER PURCHASE IN 2012 AND HAVE BEEN DEALING WITH THIS PROBLEM FOR 7 YEARS. JUST RECENTLY, HAD TOYOTA INSTALL 1/4" HARDWARE CLOTH OVER THESE 3 AREAS AND THIS SHOULD HELP SIGNIFICANTLY TO PREVENT ENTRY. ALL PREVENTATIVE MEASURES TO PREVENT MICE ENTRY HAVE BEEN DILIGENTLY TAKEN BY ME, WITHOUT SUCCESS. MICE CAN MAKE A PERSON VERY SICK. THEIR EXCREMENT CARRIES HANTAVIRUS..... AND THE MICE CARRY TICKS, WHICH CAN LEAD TO LYME DISEASE. SIMPLY MANUFACTURING THE CAR WITH THESE VENTS PROPERLY SCREENED WOULD GREATLY REDUCE THE CHANCE OF OCCUPANTS CONTRACTING A SERIOUS DISEASE.THE MICE ALSO DO A LOT OF DAMAGE TO THE CAR ITSELF, IN MY CAR THE DRIVER SEAT BELT WAS CHEWED, AND I HAVE HAD TO REPLACE THE CABIN AIR FILTER SEVERAL TIMES BECAUSE OF NESTING IN THIS COMPARTMENT(AFTER HAVING BEEN UNKNOWINGLY BREATHING THE MICE EXCREMENT AS THE AIR PASSES THROUGH THIS FILTER ON ITS' WAY TO THE INTERIOR. TOYOTA NEEDS TO BE PRESSURED BY YOUR AGENCY TO CORRECT THIS VERY SERIOUS HEALTH HAZARD THAT THEIR CAR IS PRESENTING. THEIR IS NO LEGITIMATE REASON FOR THIS SITUATION TO EXIST. THE COST TO TOYOTA WOULD BE NEGLIGIBLE.THE BENEFIT TO ALL PRIUS OWNERS WOULD BE VERY SIGNIFICANT, LIKELY PREVENTING MANY CASES OF DISEASE. PLEASE TAKE THIS SITUATION VERY SERIOUSLY, AS IS THE CASE. I ALSO WILL BE CALLING YOU TO DISCUSS THIS OVER THE PHONE. THANK YOU FOR YOUR HELP TO CORRECT THIS PROBLEM!

I am writing to bring attention to a critical safety issue affecting the 2012 Toyota Prius and other Toyota models equipped with the brake booster and actuator system. These components are failing at alarming rates, leaving vehicles with no functional brakes, ABS, or traction control. Additionally, this failure compromises the hybrid system due to the regenerative braking no longer working, potentially causing further damage to hybrid components and resulting in repairs costing several thousand dollars. Toyota issued Customer Support Program ZJB, which covered these issues for a limited period. This program was in effect from August 31, 2021, with no mileage or year restrictions, but offered secondary coverage for up to 10 years or 150,000 miles from the vehicle’s first use. Unfortunately, my vehicle, with approximately 130,000 miles and 12 years of age, was denied coverage when brought to a dealer after the program had ended. Despite the brake booster and actuator failing, the dealership did not advise me not to drive the vehicle, further emphasizing the gravity of this oversight. This is a significant safety hazard, as vehicles with these failures lack the ability to stop effectively, risking lives on the road. Furthermore, this problem is not isolated to my Prius; it affects thousands of Toyota vehicles equipped with these components. The estimated repair cost exceeds $3,000, an undue burden on owners for an issue that stems from defective manufacturing. I firmly believe Toyota’s decision to address this problem through a limited Customer Support Program, rather than a full recall, is inadequate and irresponsible. This issue meets the criteria for a safety recall and should be treated as such by the National Highway Traffic Safety Administration (NHTSA). I respectfully urge the NHTSA to investigate this matter further asap/mandate a recall for all affected vehicles. This is a big safety issue. [XXX] [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)

The contact owns a 2012 Toyota Prius. The contact noticed that there was a significant amount of water on the floorboards from the windshield whenever it rained heavily. Additionally, the contact stated while at a traffic sign on a hill, the vehicle would roll backwards while in drive when she took her foot off the accelerator. The contact did not notice any warning lights. The contact also noticed that while parking the vehicle, whenever the PARK button on the dashboard was not depressed while the vehicle was running, the vehicle would roll forward. The contact took the vehicle to the local dealer, where it was not diagnosed and was not yet repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 80,000.

Unknown. There were a multitude of codes that appeared on the diagnostics causing problems with engine. The temperature, brake, tire sensor lights are all on. The cruise control is not working. White smoke emitting from tail pipe and engine. Main engine coolant leaking. Car overheating rapidly.

The contact owns a 2012 Toyota Prius. The contact stated that while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. The contact stated that the check engine and the hybrid warning lights were illuminated, and the vehicle decelerated. The contact received notification of NHTSA Campaign Number: 18V684000 (Hybrid Propulsion System). The vehicle was taken to the dealer; however, the contact was informed that parts were not yet available for the recall repair. The contact was informed that the parts might be available within a week. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 137,000.

I was driving on highway & the vehicle stopped accelerating as I was pressing the gas. I put my hazards on & got to the side of the road. Then the eps light came on & the dash stopped showing the mph. The ac stopped blowing cold air & the windows were working slow. I turned car off then back on a couple of times then more lights came on. No lights were on prior to this & I haven’t had any problems w the vehicle before this. I just got this car & I feel like it has something to do with a recall but no one wants to take responsibility for the issue.

The contact owns a 2012 Toyota Prius. The contact stated that after starting the vehicle, the vehicle lost brakes and power steering functionality. The traction control, ABS, and braking system warning lights were illuminated. The vehicle was towed to the local dealer and was diagnosed with brake booster failure. The vehicle remained at the dealer and was not yet repaired. The manufacturer was notified of the failure. The contact related the failure to NHTSA Campaign Number: 13V235000 (Service Brakes). The approximate failure mileage was 80,000.

VEHICLE IS MANUFACTURED WITHOUT ANY REGARD FOR PREVENTING MICE FROM ENTERING THE PASSENGER INTERIOR--- AIR INTAKE VENT UNDER WINDSHIELD AND 2 REAR DECOMPRESSION VENTS LOCATED IN THE REAR CARGO COMPARTMENT ABOVE THE WHEEL WELLS ARE OPEN TO THE EXTERIOR ALLOWING UNIMPEDED ACCESS TO THE INTERIOR OF THE CAR. HAD MICE IN THIS CAR 2 WEEKS AFTER PURCHASE IN 2012 AND HAVE BEEN DEALING WITH THIS PROBLEM FOR 7 YEARS. JUST RECENTLY, HAD TOYOTA INSTALL 1/4" HARDWARE CLOTH OVER THESE 3 AREAS AND THIS SHOULD HELP SIGNIFICANTLY TO PREVENT ENTRY. ALL PREVENTATIVE MEASURES TO PREVENT MICE ENTRY HAVE BEEN DILIGENTLY TAKEN BY ME, WITHOUT SUCCESS. MICE CAN MAKE A PERSON VERY SICK. THEIR EXCREMENT CARRIES HANTAVIRUS..... AND THE MICE CARRY TICKS, WHICH CAN LEAD TO LYME DISEASE. SIMPLY MANUFACTURING THE CAR WITH THESE VENTS PROPERLY SCREENED WOULD GREATLY REDUCE THE CHANCE OF OCCUPANTS CONTRACTING A SERIOUS DISEASE.THE MICE ALSO DO A LOT OF DAMAGE TO THE CAR ITSELF, IN MY CAR THE DRIVER SEAT BELT WAS CHEWED, AND I HAVE HAD TO REPLACE THE CABIN AIR FILTER SEVERAL TIMES BECAUSE OF NESTING IN THIS COMPARTMENT(AFTER HAVING BEEN UNKNOWINGLY BREATHING THE MICE EXCREMENT AS THE AIR PASSES THROUGH THIS FILTER ON ITS' WAY TO THE INTERIOR. TOYOTA NEEDS TO BE PRESSURED BY YOUR AGENCY TO CORRECT THIS VERY SERIOUS HEALTH HAZARD THAT THEIR CAR IS PRESENTING. THEIR IS NO LEGITIMATE REASON FOR THIS SITUATION TO EXIST. THE COST TO TOYOTA WOULD BE NEGLIGIBLE.THE BENEFIT TO ALL PRIUS OWNERS WOULD BE VERY SIGNIFICANT, LIKELY PREVENTING MANY CASES OF DISEASE. PLEASE TAKE THIS SITUATION VERY SERIOUSLY, AS IS THE CASE. I ALSO WILL BE CALLING YOU TO DISCUSS THIS OVER THE PHONE. THANK YOU FOR YOUR HELP TO CORRECT THIS PROBLEM!

THE DRIVER SEATBELT BUCKLE WILL NOT UNBUCKLE

While driving, the vehicle experienced a sudden brake system malfunction without prior warning or gradual degradation. The vehicle was being operated under normal driving, road, and weather conditions. No recent brake service, repairs, or aftermarket modifications had been performed prior to the failure. Multiple warning lights illuminated on the dashboard, including the ABS warning light, brake warning light, and traction control warning light. Shortly after the warning lights appeared, the vehicle began emitting continuous warning beeps. Audible buzzing or pumping noises were also present from the brake system during the malfunction. During this event, brake performance was reduced and braking felt inconsistent. The brake pedal became hard at times and spongy at other times, requiring increased effort to slow the vehicle and resulting in unpredictable braking response. This created a safety concern while the vehicle was in motion. The driver was forced to alter driving behavior and exercise extreme caution due to reduced braking confidence and unpredictable pedal feel. The malfunction has occurred intermittently during normal driving. The condition temporarily resolves on its own and later reoccurs without corrective action. The suspected failed component is the brake actuator / ABS actuator assembly. A diagnostic scan retrieved fault codes C1252 (Brake Booster Pump Motor ON Time Abnormally Long), C1253 (Pump Motor Relay Malfunction), and C1256 (Accumulator Low Pressure), which are consistent with brake actuator malfunction. The failure occurred at approximately 154,000 miles. This vehicle model and generation have a documented history of premature brake actuator failures with similar safety-related symptoms reported by other owners. The condition places the driver and others at risk due to unpredictable braking behavior, reduced braking effectiveness, and repeated warning alarms while driving. Warning lamps and audible alerts continue intermittently.

I was driving my 2012 Prius on the highway at around 55 MPH. The Hybrid System Warning came on and the car lost all power and immediately began to coast. I was fortunate not to have been in or caused an accident but cars behind me had to swerve to avoid hitting me. I was able to coast to a middle median lane. After waiting 15-20 minutes, the car never regained power. We were finally able to push it off the road and into a parking lot. It never regained power.

The contact owns a 2012 Toyota Prius. The contact stated that while reversing, the driver's side rear wheel flipped over. The vehicle was towed to the dealer, where it was diagnosed with a corroded I-Beam assembly on the rear wheel. The contact was informed that the driver's side rear hub and the BRG assembly, rear suspension, and bolts needed to be replaced. The vehicle was repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 196,347.

2012 Prius in very good condition with 180k miles- only 12 years old. Driving on back roads (thankfully) and the drivers side rear wheel compelely fell off while driving. I was doing about 30 MPH and felt like there was a flat tire so I was in the process of pulling over when the whole rear assembly snapped. The wheel hit the rear quarter of the car and bounced about 100 feet down the road. I could have been on the highway and this could have been fatal I believe. Very, Very scary. As can be seen in attached photos the issue was rust from the inside. This is very concerning since there was no way for me to know this was an issue. I could have been killed or killed someone else. I believe Toyota needs to look into this since there are other Prius' out there the same thing happened to on this very thread. Although this is a Massachusetts car I have owed it since 25k miles and have maintained it impeccably. I always have the undercarriage cleaned after driving on salty roads. Safety inspection was current- only done the month before. Had that wheel bearing replaced about 2 weeks before the incident and the reputable mechanic reported no issues. There was no warning except for maybe a minute before it happened- the car was vibrating like I had a flat tire. The damage repair estimate on this was $8500. Catastrophic fail Toyota. Is this a rust issue like the Tacoma, Tundra, and Sequoia?????

MY WIFE WAS INVOLVED IN A TWO CAR CRASH WHEN A CAR COMING IN THE OPPOSITE DIRECTION MADE AN ILLEGAL LEFT TURN DIRECTLY IN FRONT OF HER. IT HAPPENED SO QUICK THAT SHE NEVER HAD TIME TO HIT HER BRAKES. SHE WAS TRAVELING BETWEEN 30 AND 35 MPH IN A 35 MPH ZONE ON A TWO LANE ROAD. I WOULD THINK THAT AT THAT SPEED IF ALL HER SAFETY EQUIPMENT WORKED SHE WOULD NOT SUFFER ANY INJURIES. HER SEAT BELT FAILED CAUSING THE SEAT LATCH TO FAIL AND SHE ENDED UP JAMMED INTO THE BOTTOM AND UNDER SIDE OF THE DASHBOARD. SHE SUFFERED A BLOW TO HER CHEST AND INJURIES TO HER KNEES, LOWER LEGS AND FOOT. SHE HAD SURGERY ON HER RIGHT KNEE SO WE COULD GET HER ON HER FEET AGAIN AND IS AWAITING SURGERY ON HER RIGHT SHOULDER. SHE HAD A PRE EXISTING HEART CONDITION THAT WAS RAISED TO EMERGENCY STATUS AFTER THE BLOW TO HER CHEST AND SHE HAD SURGERY FOR THAT AND THEY FOUND A SHORT CIRCUIT IN THE MIDDLE OF HER HEART AND ZAPPED IT. THERE IS ONLY A 2% CHANCE IT WILL EVER RETURN. I HAVE PICTURES OF THE FAILED SEAT BELT AND SEAT. THE SEAT BELT IS IN THE FULLY EXTENDED POSITION AND LOCKED AND CAN NOT BE RELEASED EVEN BY YANKING ON IT. I AM WRITING THIS REPORT SO THIS SITUATION CAN BE CHECKED AND IF FOUND FAULTY CAN BE CORRECTED BEFORE ANY ONE ELSE GOES THROUGH WHAT MY WIFE IS GOING THROUGH.

I AM 5'3". THE HEADREST OF MY CAR IS DESIGNED TO ANGLE FORWARD AT THE TOP. THIS PUSHED MY HEAD DOWN AT A 15* ANGLE. IT IS PAINFUL TO DRIVE. I WILL HAVE TOREMOVE THE HEADREST COMPLETELY, LOSING ANY PROTECTION IN ANY ACCIDENT AND LOSING THE SUPPORT IT SHOUD GIVE MY HEAD NOW. I UNDERSTAND THIS DESIGN IS MANDATED BY YOUR AGENCY AND THAT ALL PEOPLE IN THE 5'0" TO 5'4" HEIGHT RANGE EXPERIENCE THIS PROBLEM. SINCE THE AVERAGE HEIGHT FOR AMERICAN WOMEN IS 5'5" YOUR REGULATION DISCOMFORTS AND/OR ENDANGERS HALF OF THE WOMEN IN THE COUNTRY. CHANGE THE REGULATION. ALLOW, OR REQUIRE, HEADRESTS THAT CAN SWIVEL TO CHANGE THE ANGLE OF ALIGNMENT.

On three of the four tires at different times the tires were separating. They had bulges in the tire. Caused extreme vibration and noise. The last tire was today with 22k miles. The other two were a year ago with 15k miles. I’ve had to replace all 4 tires

TL* THE CONTACT OWNS A 2012 TOYOTA PRIUS. THE CONTACT STATED THAT AFTER THE VEHICLE WAS PARKED IN A RESIDENTIAL GARAGE, IT STARTED TO ROLL AWAY IN REVERSE INDEPENDENTLY. THE CONTACT STATED THAT THE VEHICLE ROLLED ALL THE WAY INTO THE STREET KNOCKING HER DOWN TO THE GROUND AND INTO A MAIL BOX. THE CONTACT SUSTAINED A LACERATION TO HER LEFT LEG WHICH REQUIRED MEDICAL ATTENTION. THE DEALER WAS NOT NOTIFIED OF THE FAILURE. THE VEHICLE WAS REPAIRED. THE APPROXIMATE FAILURE MILEAGE WAS 23,900. *TR