2013 Toyota Prius

While driving on a highway overpass, the brake booster system suddenly failed in my 2013 Prius on March 12, 2024. The vehicle displayed Diagnostic Trouble Code (DTC) 1391, which is a known issue with Toyota Prius vehicles. Toyota offered an extended warranty for this repair that expired in August of 2023, admitting that their vehicles contained faulty parts. There have been several complaints about this known issue and an investigation needs to be reopened regarding this ongoing issue. Will someone from the NHTSA please start an investigation or facilitate in any way to get an investigation into to this reoccurring issue. Brakes matter and society is depending on government and corporations to be transparent and ethical. The FTC, BBB and Attorney General’s need to act on behalf of everyone in keeping our roads safe and holding Toyota accountable again. This is absolutely a major safety issue that should be covered by Toyota regardless of when it manifests.

- The Hydraulic Brakes, or brake actuator, failed. I have taken it to my local mechanic and they confirmed. - My brakes are operating at a substantially reduced capacity - an emergency mode that only allows for the front brakes to work - Yes, my local mechanic confirmed the problem - It has only been inspected by my local mechanic - yes, several warning lights came on while I was driving.

The brake pump which pressurizes the nitrogen accumulator kept cycling on more and more frequently until it was cycling on every 8 seconds after stopping while trying to maintain pressure in the automated brake system. Brake pressure began pulsating when applying brakes and was slowly becoming noticeably more unstable as time progressed. I could also hear a steady flow of fluid through the booster/master cylinder unit. This seems to be a common issue often being discussed online in forums like “Prius Chat”, an online car community describing the characteristics of the power brake system in this vehicle before it fails as well as with a number of online youtube mechanics replacing these units. It seems as though the solution is for dealerships to charge in many cases more than 4000 dollars to replace both the entire “Brake Booster Assy, w/Master Cylinder” and the “ Pump Assy, Brake Booster” as standard procedure. I believe it’s the ‘Brake Booster Assy, w/Master Cylinder’ unit causing the issue, I do all my own repair work on my vehicles and I partially disassembled the booster/master cylinder unit, upon removing the cover for the circuit board control unit integrated into the assembly I discovered evidence of an overheated or corroded circuit board. The soldered pins for the main bus connecting the wiring harness to the circuit board showed possible charing and discoloration as well as very dull colored soldered joints. This was also observed at the bottom of the circuit board as well. After replacing both assembly units in the vehicle the brakes work flawlessly again. I was told by the parts salesman at the local Toyota dealership that he had been selling a lot of these replacement units lately.

Power brake, electronic systems around braking, brake actuator and assembly. Gradual degradation of brake power and resistance resulting in complete loss of power brakes system. Vehicle's brake system no longer works as designed. Vehicle has been inspected by technician. No warning lights or lamps in advance of total brake system shut down.

Loss of brake function coming to a red light. 5 warning lights illuminated. Also noticed a noise that appears to be coming from the brake pump that is cycling every 3-4 seconds. 1) Masterv Warning Light. 2) Brake System Warning Light 3) Brake System Warning Light 4) ABS Warning Light 5) SLIP Indicator I have called the Toyota service advisor and will be getting a quote for repair. Apparently, I have found out that there is a class action inquiry that I would like to be included in.

Several dashboard lights came on suddenly when braking. Upon speaking with the dealership it was determined that I experienced sudden brake actuator failure resulting in loss of braking power. Fortunately, it was not complete loss of braking or it could have been dangerous to myself and others on the road. Upon researching this issue, I have discovered that brake actuator failures are not uncommon in Toyota Prius models, and there have been numerous reports and complaints from other owners facing similar problems. This raises serious questions about the integrity of the brake system in these vehicles and the potential for widespread safety hazards.

The brake booster system suddenly failed in my 2013 Prius. I was driving when the ABS warning light, the brake warning light, and slip indicator light came on. The brakes became soft and it was difficult to stop the vehicle. I had it towed to a local, independent mechanic and the entire brake assembly had to be replaced. Toyota offered an extended warranty for this repair that expired in August of 2023, admitting that their vehicles contained faulty parts. This is absolutely a major safety issue that should be covered by Toyota regardless of when it manifests.

As I was driving, the ABS, Brake, and Traction Control lights all illuminated on my dashboard and have remained on since. I took the car into the dealership to get a diagnosis, and they told me that I had a accumulator leak and needed to repair my brake master cylinder and replace the brake booster pump assembly. This is apparently a known issue with Toyota Prius, as hundreds of others have discussed this in various forums.

I am the joint title owner of a 2013 Prius. This complaint is Case # [XXX] at Toyota. Our [XXX] daughter has full-time use & possession of this vehicle. In her own words, this is what happened: “I was driving on the [XXX], about to merge onto the [XXX] in Los Angeles. This is an extremely traffic-heavy interchange. Approaching the stopped car in front of me, I applied my brakes. The brakes did not work properly. I had to press the brake pedal much harder than I normally do, & my car kept going for another two seconds or so before stopping. Three dash lights came on – ABS light, brake light, & light with the swerving car symbol. There was a ‘puffing’ type of sound from the brake pedal that lasted about a second, then stopped for about two seconds, then started again, & so on. That sound would come out of the pedal area regardless of whether I applied the brakes. Frightened by the brake failure, I pulled off the freeway in downtown L.A. I turned the car off & let it sit for a few minutes. When I turned it back on, the same three dash lights came back on, & the car was still not braking properly – still the delay, the need to press harder than usual, & the sound. I drove directly to my Toyota dealer. It was a 35-minute, nerve-wracking trip.” The dealer found "CODE C1391 ABNORMAL LEAK IN ACCUMULATOR." Cost of repair was $3,163.12. Note also that in 7/23, she had taken the car to the dealer with the "SAME sound" (her words) when braking. The dealer could not duplicate the problem. They did not conduct a brake test at that time. Online, I discovered that this serious safety issue had been raised in a previous petition, investigation, & customer support program that expired. This problem is the subject of a CURRENT, OPEN, NHTSA Action, # DP23005. Toyota knew of this problem, instituted a program due to safety risks from C1391, allowed the program to expire, & has left us at risk without warning. Our other daughter owns a 2014 Prius. This needs recall. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOI