Which parts fail
Components named in complaints (service brakes, ABS, rotors and pads, parking brake).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2004 Toyota Prius owners, lightly cleaned up (personal details are redacted by NHTSA).
Toyota has issued time-limited 'Warranty enhancement program ZG1' instead of working with the NHSTA to issue a comprehensive BRAKE ACTUATOR ASSEMBLY RECALL. ZG1 was explicitly in place only from April 2016 to Dec 2017, requiring dealer verification of an actual system failure prior to 31 Dec 2017. My failure occurred in 2021 and Toyota will not extend ZG1 for me (case 211015000390). Obviously the BRAKE ACTUATOR is a key safety component. Obviously this is a design flaw - brake systems MUST be designed to last the life of the vehicle. Obviously Toyota has had an excessive number of failures. Toyota is improperly using this 'warranty enhancement program ZG1' to avoid the NHSTA and to avoid responsibility for the poor BRAKE ACTUATOR ASSEMBLY design. Per their letter to owners, Toyota was NOT replacing the BRAKE ACTUATOR ASSEMBLY on a preventive basis prior to actual brake failure. …
When stopping suddenly sometimes the brakes on my 2004 Prius would not respond immediately as they should. They would release the calipers completely and the only way to stop would be to let off the brakes and press them again. It does not happen often but it is regular enough that this has always concerned me very much. Today I was following a car who slammed on their brakes very suddenly and therefor I also had to slam on my brakes. This same issue occurred and I did not have time to release the brakes and press them again causing me to hit the back of the car that I was following. I maintain my cars very well and this car was in top condition with brand new tires. The brakes do not even activate enough to squeal or leave any rubber behind. There is no way that I could possibly have stopped in time. This is not safe and needs to be resolved for other people who have these cars.
Tl* the contact owned a 2004 Toyota Prius. While driving approximately 15 MPH and while attempting to stop the vehicle by depressing the brake pedal, the brakes malfunctioned and the vehicle crashed into the rear of an SUV. The contact sustained multiple toe injuries on the right foot, including one fractured toe. Medical attention was required. A police report was filed. The vehicle was destroyed. The cause of the failure was not determined. The manufacturer was not notified of the failure. The failure mileage was 205,000.
Tl contact owns a 2004 Toyota Prius. While driving approximately 55 MPH the vehicle accelerated on its own. The vehicle crashed into a concrete divider on the highway. The contact stated that the air bags did not deploy. The contact was able to drive the vehicle after the crash. The driver and the passengers sustained injuries to their back and neck and were under going therapy for their injuries. There was no police report filed. The contact stated that the crash caused damage to the front bumper and the front passenger side door which would not open. The manufacturer stated that an inspector would inspect the vehicle. The inspector stated that there was a problem with the ABS brakes. The contact received the report from the manufacturer and they did not indicate that there was a safety failure and were unable to provide further assistance. The body damage was repaired. …
My Prius suddenly had a 70 to80% loss of brake power. My parking brake light came on along with the ABS, vcs, the red triangle and a load buzzer. If this had happened at highway speed I could have rear-ended or killed someone. After turning my car off and letting it sit the lights stayed off. This concerns me because it could lead to a false sense there's nothing wrong. I took my car to the dealer and they seemed to know right away it was the ABS brake actuator code c1256. I did some digging and it seems this is a very common problem and yet it's not a recall issue. I want everybody to know this is a safety issue. My Prius was bought new by my senior parents, they kept it garaged and only had 45000. Miles on it when I bought it from there estate. At the time the malfunction ac cured it still only has 72456. Miles on it. …
I was driving the Prius on city streets in rain. I came to a stop and started to drive and a bunch of emergency lights and beeping started. There was no unusual noise or grinding until I applied the brakes. The brake pedal was hard and had significantly lost braking power. All lights and beeping continued after turning of and restarting the Prius. I took it to a certified Toyota dealership and the diagnosed the problem as a bad brake actuator. As being a Prius owner I've done my research and know this is a very common problem with these cars and that 9 months ago Toyota was replacing this part for free. I feel like Toyota needs to address this problem as my Prius only has 80K miles and a 3 thousand dollar repair is pretty outrageous for a car that hasn't even hit 100K miles.
Dt: the contact owns a 2004 Toyota Prius. The contact complained about brake problems. The contact stated the pedal hit a stop before locking the wheels to brake. The contact complained about the vehicle to the service dealership and they did check brakes on this vehicle as well as other vehicles of this make and model, but s it was a normal braking procedure with this vehicle. The dealership replaced the brake pads. The contact stated when he pressed the brakes,there was a minimum braking capability in stop and go traffic. The consumer hit a vehicle that was in front of his vehicle because he could not stop it. The contact did not have mechanical knowledge, and did feel this was a problem, even though the dealership stated there was no problem.
I was coming off of an onramp and intending to turn right at the light. I needed to get into the left lane as I was turning left at the next block. I applied the brakes to slow down and make the turn and nothing happened when I pressed on the brakes. I ended up going up over the curb and the plants stopped the car. The engine was off when I came to a stop, though I didn't turn it off. If there hadn't been a meridian in between the cross traffic, I would have gone into the lanes ahead of me. Very scary. I had my car towed to Toyota to check it out first, but there looks to be thousands of dollars of damage to my Prius. The whole lower front is smashed and crunched, the two left side tires are flat and the rim is partially torn off on the front tire.
Tl contact owns 2004 Toyota Prius. While driving downhill out of her driveway, she depressed the brake pedal and the brakes would not engage. The vehicle proceeded to crash into a nearby tree at unknown speeds and continued to push the tree further into the street. The contact's foot remained on the brake pedal; however, the vehicle would not stop. There were no injuries. The police arrived and a report was filed. The police observed skid and brake marks in the driveway, confirming she was attempting to brake at the time of the crash. No repairs were made to date. The contact was unaware if the vehicle was under recall at the time. The VIN was not available. The failure and current mileages were 50,000.
Tl contact owns a 2004 Toyota Prius. The contact was driving approximately 25 MPH on a gravel road. Pressure was applied to the brake pedal and there was no power response. The vehicle failed to slow down and crashed into another vehicle. The opposing vehicles driver, and passengers sustained moderate injuries. The police was called to the scene. The brake system failure occurred intermittently prior to the crash. The vehicle was taken to an authorized dealer for an estimate of the body damages. Currently, the vehicle was being repaired at an auto body shop. The cause of failure has not been determined at this time. The failure mileage was 186,000.
Brake complaints in other Prius years
Frequently asked questions
How common are brake problems on the 2004 Toyota Prius?
NHTSA has 76 complaints about the brakes of the 2004 Toyota Prius, 12% of the model year's 610 complaints. The component named most often is antilock/traction control/electronic limited slip (9 mentions).
Is there a recall for 2004 Toyota Prius brake problems?
No. NHTSA lists no brakes recall for the 2004 Toyota Prius, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2004 Toyota Prius brake problems start?
Half of the complaints with a recorded mileage happened before about 84,000 miles, and 18% before 25,000 miles.
Is it dangerous?
Owners linked 11 crashes, 0 fires and 9 injuries to brakes problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.