2012 Toyota Prius C Brakes Problems

While driving 65 mph on the expressway on January 12th, 2026 under cruise control, I tapped my brakes to slow down. My brake warning light came on, along with the ABS warning light, and the anti-swerve warning light. Cruise control no longer worked, and my brakes were noticeably hard to apply. I immediately had the vehicle computer checked and the issue is a leaking brake booster component, a faulty part known by Toyota to fail prematurely with this and other Prius models. No recall was issued however. The car is now unsafe to drive until a ~$4000 repair is done, according to my service representative.

NHTSA ID

11712556

Incident

Jan 12, 2026

Brakes went soft with little braking power. Traced the fault code to a faulty braking actuator; toyota says this is past the coverage date for the recall.

NHTSA ID

11707563

Incident

Dec 26, 2025

I own a 2012 Toyota Prius C with approximately 156,578 miles. The vehicle has been diagnosed with C1391 – Abnormal Leak in Accumulator, which causes the brake actuator to lose hydraulic pressure. This results in frequent buzzing from the actuator pump, illuminated warning lights (BRAKE, ABS, Traction Control), and loss of ABS and stability control. The condition increases stopping distance and creates a serious safety hazard. Toyota previously acknowledged this exact defect under Customer Support Program CSP 21TE01, which covered brake booster and pump assemblies for certain Prius and Prius C models when codes such as C1391 were present. However, the program expired on November 30, 2022, and my vehicle is just over the 150,000-mile coverage limit. Despite this, my Prius exhibits the same defect that Toyota has already recognized as a safety-related issue. Toyota Carlsbad confirmed the diagnosis and quoted $3,399.55 plus tax for repair, with a reduced courtesy estimate of $2,817.86 plus tax, but declined goodwill assistance since CSP 21TE01 expired. Given the widespread reports of brake actuator failures in Prius models, I believe this represents a systemic safety issue that warrants NHTSA investigation and potential recall/extended coverage.

NHTSA ID

11681477

Incident

Aug 14, 2025

Brake Actuator and ABS Accumalator failed. It is a common failure reported by multiple owners on these cars. I was on the high way going 70 when it failed and lost any brake boost I had putting me in a very dangerous situation where I narrowly avoided an accident. Upon scanning the car's codes I got code C1391 which I looked up and saw a bunch of other people who were also struggling with this issue.

NHTSA ID

11673785

Incident

Jul 10, 2025

I am writing to express a complaint regarding the issues I have experienced with the brake system of my Toyota Prius C, 2012 model. For the past several months, I have noticed that the brakes exhibit strange noises, soft pedal sensation, reduced braking efficiency, were driving and the ABS, traction, brake, and that other light turned on and the brakes became slow these issues have been observed on multiple occasions and pose a safety risk to myself, other drivers, and pedestrians. I have taken the vehicle for inspection, but the problems persist or have not been definitively resolved. I believe these faults may be related to defects in the braking system, and therefore I request a thorough inspection and necessary repairs at no cost, considering that the manufacturer could be responsible for manufacturing defects.

NHTSA ID

11664280

Incident

May 3, 2025

The brakes on this Prius started to make weird noises. Because it is a hybrid, I wasn't sure if it was normal. After searching online, it is a known issue. The car has just under 76,000 miles on it. It might be worth $7000 on a good day. Toyota wants to replace two brake parts, numbered 47050-52020 and 04006-74152 to a tune of $2700. According to a Toyota bulletin, this job should take 2.3 hours. For that amount of work, my local Toyota shop wants almost $2000 in labor. My car was seen by the local shop (being on an island, it is literally the only Toyota shop that this car can be seen) when the "customer support program" 21TE01 was in place and they did nothing. Now, the time window has disappeared, even though we only have half of the maximum number of miles to get the repair. Toyota should be ashamed of themselves.

NHTSA ID

11643434

Incident

Feb 17, 2025

My ABS actuator failed. Turns off the boosted braking and cruise control. This is a known issue in Toyotas and it always happens outside the warranty window. This is putting my safety at risk as the brakes don’t work as they’re supposed to

NHTSA ID

11638598

Incident

Dec 29, 2024

I was driving down the interstate with my cruise control on when all of a sudden the cruise control disabled and warning lights came up on my dash board. It still drove fine for several weeks. On Friday December 6th, I was going down the road and had to press the brake slightly for a car turning. When I pressed the brake, the car went into a spin. It spun a couple of rotations. Luckily I was on a wide part of the highway and no oncoming cars were approaching. Toyota had a recall for the same code and parts for the 2010 Prius but did not include the 2012 Prius. They just had an alert which I did not receive because the notice went to the former owner. However, I did take my car in for oil change and diagnostic but they did not tell me that there had been a problem with these parts. They want almost $4,000 to repair it. Why would they not include ALL vehicles with this same part. If it fail on one, it will fail on another. I think Toyota should make them all good. Please make them issue a recall for all of these parts. I took my car to a mechanic but because of special tools needed, you have to take your car to the dealership for repairs. When I called the dealership, I was told I needed a break booster pump and a brake master cylinder for a total of $3, which is ridiculous on a $7,000 car.

NHTSA ID

11630042

Incident

Dec 6, 2024

While my daughter was driving brake pedal faded and rear brakes locked up causing her to lose initial control of car . Steering felt tight . Many warning lights , check hybrid system , brake lights , steering warning lights , along with abs lights came on . Took car to Toyota dealer to diagnose it needs brake booster and master cylinder module . Service consultant said known issue with TSB but it had expired . Many , many complaints of this same incident of Toyota and Prius forums .

NHTSA ID

11597788

Incident

Jun 21, 2024

Code C1391 shows in which the accumulator and the brake booster assembly need to be changed. This is a known defect and was covered through an ‘extended warranty’ due to a lawsuit. Since it results in less than optimal braking, and can result in crashes since function disappears suddenly, it should have warranted a recall. This issue is also known to happen in multiple Toyota hybrid vehicles.

NHTSA ID

11576687

Incident

Jan 13, 2024

The brakes fail and the ABS module stops working correctly and when I go at a speed of 60 MPH the brakes lock until the speed drops and they work again. The problem is with the ABS module and I went to the dealer and the repair value is $3450 dollars.

NHTSA ID

11549504

Incident

Sep 10, 2023

Last week my 2012 Toyota Prius-C had four lights come on (ABS, Brake, Swerve, and one other). I took it to my local mechanic who informed me that it was my master cylinder brake that needed to be replaced and would cost me $3,300. This issue started roughly 10-12 months ago, when I heard my brakes making a noise that sounded very unusual, almost like a hydraulic issue. I learned that there was a Toyota initiated CSP. Toyota realized there was an issue with the 2012-2014 brake system that affected over 100,000 vehicles. Those affected by CSP's are supposedly notified by mail. Needless to say, I never received such notice. This aforementioned CSP expired in November 2022 that my car would have qualified for, had the problem been diagnosed prior. However, when I brought my car in on August 8th, 2022 for my hybrid battery, a diagnostic was done on my brake system with no indication that my brake system was in trouble. I really can't fault the mechanics at the local Toyota, I took it to a second brake specialist a few months after and they too could not identify the problem. The problem was so bad, Toyota discontinued the brake system. Toyota said it would need to be broken 100% with an error message to qualify prior to the November 2022 deadline. After being facetious and saying I should have broken the part myself to qualify, she said that is what I would have needed to qualify.

NHTSA ID

11526268

Incident

Jun 3, 2023

Without prior warning brake pedal goes to floor before minimally engaging braking system at a very reduced rate causing me to swerve and narrowly avoid collisions on interstate. There is no pressure feeling in the brake pedal although brake fluid level is normal and inspection of brake pads indicated significant pad available. No DTC light is coming on and OBD scan tool indicates no brake error. Brakes are unable to stop car to avoid collision, so car is dangerous and undrivable.

NHTSA ID

11520747

Incident

May 5, 2023

a warning light came in on my dashboard brakes regarding the Brake pump accumulator. It feels like my brakes are not working right, not stopping like they always did.I was scared I almost hit someone in front of me at a red light because after applying the appropriate notes due on the brake pedal I noticed a delay in the car stopping. I had the brakes checked by a mechanic and they are ok. This is very dangerous. Can the manufacturer be required to repair this defect? Thank for your help.

NHTSA ID

11457814

Incident

Mar 14, 2022

My brakes gave out while driving with my infant child luckily I was almost home and made it without hitting anyone or seriously hurting myself and my child. Had car diagnosed error code c1256. Local dealership won’t repair because I “missed “ recall and my car has salvage title. I cannot afford to fix on my own and I’m shaking as I drive with my child to work everyday praying to get there in one piece because I have to work…

NHTSA ID

11445845

Incident

Dec 6, 2021

IGUALMENTE QUE LOS CARROS PRIUS REGULARES, EL CUAL HAY UNA GARANTIA EXTENDIDA, MI EL AUTO DAO LA BOMBA DE FRENOS, LO CUAL ES MUY COSTOSA, ESTA GARANTIA SOLO ES SOLO PARA PRIUS REGULARES IGUALMENTE UTILIZAN EL MISMO SISTEMA. SE DEBE VERIFICAR PORQUE NO CUBRE LOS OTROS AUTOS YA QUE TIENEN EL MISMO SISTEMA.

NHTSA ID

11299250

Incident

Dec 24, 2019

Mileage

15,000 mi

FROM DATE OF PURCHASE, VEHICLE PERFORMED UNPREDICTABLY. TRANSITIONING FROM ELECTRIC TO MOTOR WAS ROUGH AND NOTICEABLE. AT 600 MILES, A SIGNIFICANT IMPACT WAS FELT DURING TRANSITION. DEALER FOUND NOTHING. BRAKE PEDAL TRAVELED TO THE FLOOR AND VEHICLE WENT THROUGH STOP SIGN AT LOW SPEED. ROUTE 44 TOYOTA INSISTED I NEEDED TO GET USED TO ELECTRONIC BRAKES. TOYOTA INSISTED BRAKES WORKED AS PRESCRIBED. RECENTLY, A AAA DRIVER DISCOVERED THE GROUND WIRE ON THE BATTERY WAS LOOSE. THE BATTERY WAS REPLACED AND THE VEHICLE NOW FUNCTIONS AS DESCRIBED, THE HILL HOLD FUNCTIONS AS DESCRIBED. NHTSA DID AN INSPECTION IN RESPONSE TO A DEFECT PETITION - VEHICLE DID NOT PERFORM AS DESCRIBED IN THE FEDERAL REGISTER. BRAKE PEDAL IS NOW HIGH, AS IT WAS INITIALLY. THIS VEHICLE WAS SENT FROM THE FACTORY WITH A LOOSE BATTERY GROUND AND IT WAS COVERED UP BY EVERYONE FROM TOYOTA, DEALERSHIPS TO NHTSA WHEN THE CORRECTION WAS SIMPLE. TOYOTA DOES NOT STAND BEHIND THEIR PRODUCT.

NHTSA ID

11170640

Incident

May 23, 2012

Mileage

800 mi

THE BACK BRAKES AUTOMATICALLY RELEASE AT 5 MPH WHEN DECREASING SPEED AND ONLY WHEN ITS WET OUTSIDE. THE CAR IS NOW AT 365,000 MILES AND IT IS STILL DOING IT 6 YEARS LATER

NHTSA ID

11130403

Incident

Oct 20, 2012

Mileage

1,500 mi

BRAKE BOOSTER W/ MASTER ECM COMMUNICATION MALFUNCTION -UNABLE TO COMMUNICATE AND PERFORMS ABS, ANTI SLIPPERY AND BRAKE PEDAL TO LOW. THE MALFUNCTION INCLUDES WARNING LIGHTS PANEL TO STAY ON.

NHTSA ID

10820898

Incident

Jan 14, 2016

Mileage

87,000 mi

"TAKATA REPORT" COMUNICATION CIRCUIT MALFUNCTION C 1203 ECM - BRAKE BOOSTER W/MASTER, DURING OPERATION ALL INDICATOR LIGHTS AT THE DASH WENT ON PERMANENTLY.

NHTSA ID

10820801

Incident

Jan 14, 2016

Mileage

87,000 mi

BRAKES ARE VERY SENSITIVE DURING WET WEATHER. IT TAKES GREAT EFFORT TO AVOID A SKID. ONCE THE BRAKES WARM UP THE PERFORMANCE IS NORMAL. THE DEALER RESURFACED THE FRONT ROTORS WHICH FIXED THE PROBLEM IN THE SHORT TERM. HOWEVER, THE PROBLEM IS RETURNING.

NHTSA ID

10819384

Incident

Dec 15, 2015

Mileage

40,000 mi

BRAKING OFTEN BECOMES EXTREMELY AGGRESSIVE WHEN MOISTURE IS PREVALENT. INITIAL APPLICATION IS NORMAL, UNTIL DEEPER INTO THE BRAKING CYCLE. ONCE VEHICLE IS COMMITTED TO STOPPING AN ADDITIONAL (HARD BRAKE) SURGE THEN RENDERS SYSTEM INTO BECOMING FAR TOO AGGRESSIVE. THIS IS UNDER NORMAL BRAKING SCENARIOS REQUIRING ACTIVE OPERATOR ADJUSTMENTS TO STOP NORMALLY. *TR

NHTSA ID

10653875

Incident

Oct 1, 2014

Mileage

35,000 mi

BRAKES ARE EXTREMELY TOUCHY AND GRAB WHENEVER IT IS DAMP OUTSIDE. *JS

NHTSA ID

10585791

Incident

Nov 1, 2013

WHEN STEPPING ON THE BRAKES DURING WEST WEATHER (MOISTURE IN THE BRAKES) THE REAR WHEELS LOCK UP FOR A SPLIT SECOND EVERY TIME. WHEN IT IS DRY IT DOESN'T LOCK UP BUT STILL HITS HARD.

NHTSA ID

10583756

Incident

Apr 20, 2014

CAR IN FRONT SLOWED THEN STOPPED QUICKLY AS THE CAR AHEAD OF IT ATTEMPTED TO USE THE MIDDLE LANE IMPROPERLY (NOT A TURN LANE AT THAT TIME), NOT MOVING FULLY NOR QUICKLY INTO THE LANE. CAR IN FRONT STOPPED. APPLIED BRAKES IMMEDIATELY TO THE PRIUS C TO SLOW, THEN ADDED ONE RAPID PUMP, AND ULTIMATELY PUSHED THE PEDAL TO THE FLOOR. THE PRIUS DID LITTLE MORE THAN SLOW (WITHOUT EVEN A JOLT FROM THE FIRM APPLICATION OF THE BRAKES), CAUSING A CRASH INTO THE REAR OF THE CAR IN FRONT AND SIGNIFICANT DAMAGE TO THE ENTIRE FRONT END. NO AIRBAG DEPLOYMENT. *JS

NHTSA ID

10579128

Incident

Mar 29, 2014

Mileage

25,000 mi