2011 Toyota Prius driver assistance problems

Filed May 9, 2026 · Brakes, Driver assistance · NY

2011 Prius. 80k miles. Brake booster buzz coming on every 15 seconds now. ABs, traction and brake lights on. I’ve heard of many Prius owners with the same issue. I also have another Prius with the same issue at 120k miles. Brake booster accumulator codes popping up with 80k miles. It is a safety concern as the abs brakes don’t work. Almost every Prius is effected by this.

Filed May 5, 2025 · Brakes, Driver assistance · CA

Our trac abs and brake lights came on and braking became more difficult but not totally gone. I took it to my mechanic (not Toyota dealer) and he said the codes were going off for the abs hydraulic system and it would be $3000 to fix! This is unacceptable. I feel like my safety is affected but no one else has been hurt YET. I’m trying to be proactive. they first appeared last month. No manufacturer, insurance agent or cop has inspected it. It can be inspected by appt. Please help

Filed Mar 11, 2025 · Brakes, Driver assistance · FL

Brake warning came on and wouldn’t go off. Followed by continuous beeping and now the brakes are no longer working properly. You have to force the brake all the way to the ground to even come to a rolling stop. The problem first occurred on 3/8/25. The brake actuator seems to be a reoccurring problem that Toyota addressed but is no longer fixing. It is dangerous to drive my vehicle and others have said their brakes have completely failed when this problem arose.

Filed Feb 21, 2024 · Brakes, Driver assistance · TX

The 2011 Prius has an issue known to Toyota, in which the brake booster pump fails after an indiscriminate amount of time, leading to significant loss in braking ability and control. Toyota knows of this because they issues an extended warranty coverage for these vehicles and this issue, that did not extend beyond 10 years, or 150,000 miles, whichever comes first. [XXX] ) When I was driving my car down Highway [XXX] I lost braking control completely, with a series of constant beeping starting to emit from the braking system. Luckily through mashing the brake pedal and using ebrake I was able to get the car to slow down and pull off the highway. The brakes sporadically and randomly cut in and out with the power braking, leading to uncontrolled stopping power and jerky or inactive braking. There had been lights on the dash indicating the traction system or braking system had issues but these would frequently turn off and on and didn't result in a loss of braking ability or performance and had been there a couple months. Upon taking the vehicle to a Toyota Dealership (Charles Maund North Austin) I was told it was a C1391 error regarding a failure of the brake booster pump assembly and that it would need to be replaced and reprogrammed for about 3300 dollars. After looking online I saw there were many other people with this issue, all who were unable to fix this in the given 10 year frame. Many unsuspecting second owners of this vehicle do not know that there is a hidden danger waiting for them when their power brake pump assembly fails. If I had been a less experienced driver I would've certainly crashed and Toyota, knowing of this safety concern already, should have done the right thing and issue a recall for these vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jun 1, 2023 · Brakes, Driver assistance · TN

Three lights appeared on the dashboard…code C1391. This has affected the braking system, and the traction control…and the brakes no longer regenerate the battery. The mechanic said “YOU MUST NOT DRIVE THIS CAR” until a $2,700 repair is made. There was, apparently, a service bulletin sent out in 2019, and was then extended until 2022…which we did not receive, although we’ve been at the same address since we bought the car. But our car did not develop this common issue until now…2023, and Toyota says it was not a safety recall, so they don’t need to fix it, or help us get it fixed. We believe it IS obviously a safety issue….since my brakes can go out at any moment.

Filed Feb 16, 2022 · Brakes, Driver assistance · 90,000 miles · CA

The contact owns a 2011 Toyota Prius. The contact stated while driving 50 MPH on the highway, the brake pedal was depressed but failed to respond. The contact depressed the brake pedal harder and the vehicle almost came to a complete stop. The ABS warning light, the brake warning light, and the traction control warning light illuminated. The contact stated that she exited the highway and was able to continue to drive by slightly depressing the brake pedal. The vehicle was taken to the dealer where it was diagnosed that there was an internal malfunction of the brake booster and the brake booster assembly pump. The vehicle was not repaired. The contact contacted the manufacturer and inquired about assistance with repairing the vehicle under an unknown customer satisfaction program. The manufacturer informed the contact that the failure was not a safety issue and they could not assist as the customer satisfaction program had already expired. The failure mileage was approximately 90,000.

Filed Feb 3, 2020 · Brakes, Driver assistance · 149,700 miles · OH

Traction control, ABS and brake lights came on today and brake pressure dropped severely while driving on the highway. Not safe to drive.

Filed Aug 28, 2019 · Brakes, Driver assistance · 130,000 miles · MN

My 2011 prius very recently has started making audibly noise while pressing the brake pedal, whether in motion or stopped. This noise contains continuous whirring, whining and loud clicking noise. These noises where not seen before completely. I spoke to dealer mentioning a tsb pertaining to this particular issue in specific and was told nothing can be done until it fails completely, which is bad, as I have a family of 3 and god forbid if this were to happen while driving on freeway, a serious safety hazard and toyota dealer (rudy luther) response is irresponsible. I am actually worried more now on waiting for the brakes to fail. This loud continuous clicking noises occurs the moment car is turned on and the noises lingers on for short while after the car is turned off, at moments I have to press on the brakes really harder than usual to get the car slowed and is a tremendous panicky situation. I am registering and requesting for this to be looked immediately before any catastrophe.

Filed May 26, 2019 · Brakes, Driver assistance · 180,000 miles · AL

Brake light, antilock light, vehicle stability light, and yellow trains came on. Having problem with braking. Does not not seem to brake as good. It is very dangerous when driving.

Filed May 2, 2019 · Driver assistance, Electrical · 40 miles · VA

Well I was driving and suddenly my car battery turned off and check hybrid system came on the dashboard it stopped so I parked it on side and unplug battery wires so it start working again the weird thing is that when I check to see any code but nothing came recently it was happening and one recall came for hybrid battery after that it was working fine but now this thing happened again and it was dangerous because I was in the middle of highway and car stopped.