2010 Toyota Prius: adaptive cruise control problems

Filed Mar 6, 2024 · Brakes, Driver assistance · FL

A warranty extension went out a few years back that said one might receive a "CHECK PCS SYSTEM" warning on the dash. This has happened to us, along with 7 other lights on the dash. Between the brakes being much less responsive, and all of the pre-crash warning / adaptive cruise / radar features being disabled, this could have caused an accident. The dealer checked out the car and states that the brake actuator has a leak and that it will be a costly repair - no less than $3000. This suspiciously all happened *just* outside of the warranty window (we are within the allowed number of miles but just out of time), and also suspiciously after Toyota released an upgraded version of the actuator, and *also* after a bunch of people are experiencing the same failure. Our best assessment at this time is that the brake actuators have a factory defect and that a recall should be done.

Filed Feb 7, 2023 · Acceleration, Brakes · CA

The ABS, VSC/traction control, and brake system warning lights all came on at the same time in my 2010 Toyota Prius. I almost lost control of my car's braking ability. Afterwards, the hybrid system does not perform its regenerative braking/recharging any longer. And the cruise control mode doesn't work also. The DTC from the OBD2 port is C1391 - abnormal leak in the brake fluid accumulator. I found out that this issue is widespread among Gen 3 Priuses, but Toyota has not made this officially a recall campaign, but classifies it as a "customer support bulletin." But the issue is dangerous enough that it should be a recall item. I moved homes in fall of 2018, and Toyota says it mailed out a letter about this brake issue and resulting campaign, but I never received the letter. I was totally unaware that this was a safety issue, that Toyota acknowledged it, and that this safety issue with an ongoing "recall" campaign with an expiration date. Toyota denies that this is a recall issue, and will not provide this service. I would like for the federal safety agency to reopen and investigate this issue, and make Toyota issue a general recall campaign to resolve this dangerous safety problem with the car.

Filed Sep 4, 2018 · Acceleration · 102,000 miles · FL

On two occasions, june 22, 2018 and august 15, 2018 this vehicle suddenly accelerated while using cruise control and traveling at speed on generally flat, straight, 4 lane road in good weather. I have attached documents with summaries of each event and maps showing route and terrain during the events. Hard braking slowed but did not stop the vehicle either time. Both times, after traveling some distance while braking but continuing to accelerate without my foot on the accelerator, the vehicle made a thunking noise felt through the floor of the car and suddenly stopped accelerating. In the first incident this was after about 2 miles, the second time after about a mile. After each incident I phoned the local dealership and was told that if they could replicate the event they might be able to figure it out. I reported the events to corporate toyota and an investigation was opened. The vehicle was taken to fred anderson toyota of asheville where they spent several days with the car, interacting with toyota, who was asking them to explore and test various things related to the dual pedal fail safe, the computer, snapshots of events on the computer etc. Their final judgement was that floor mats may have interfered, though it was the first thing I checked when I regained control of the car.

Filed Mar 26, 2018 · Brakes · 150,292 miles · NC

Vsc, brake, and ABS lights are on symptoms: cruise control will bump up the speed then "cancel" cruise control the ability to "set" cruise is rejected vsc, brake, ABS lights turn on no regen braking brakes need way more effort to slow/stop abrupt braking will cause a skid any help will be appreciated.

Filed Jun 8, 2017 · Acceleration, Brakes · MD

I change the brake booster twice and hace the same problem. My brake pedal loss of braking ability or slipping brakes and the warning brake, ABS and traction light permanently on, and no cruise control works at all

Filed Feb 20, 2014 · Acceleration · NY

While returning from work at 5:30 pm, 02/18/14 on highway 90 west to albany, ny, with cruise control set to 50 MPH, the accelerator pedal got stuck on my 2010 toyota prius. The pedal did not return back to its original position even when I turned off cruise control. I spontaneously tapped the accelerator pedal in the hope of releasing but did not yield any results and the vehicle maintained its speed. Applying brakes made no effect and did not curtail the car. It continued to move with almost the same speed even when brake pedal depressed. I had no control on my car in one of busiest freeways. I continuously applied the brakes and tried to merge to the right most lane with hazard blinkers on. It took more than 5 miles panic ride trying to avoid trucks and other cars to merge to the right lane. Even with the brake fully depressed, the 2010 prius did not slow down and I managed to reach the shoulder lane which had gravel & snow. Then I pressed park button and switched off the engine by pressing the power button. I could feel the wheels lock up but the prius continued to move with strong rubber burning smell. Finally, I engaged the parking breaks to stop it from moving into the freeway. After complete stop, with difficulty I manually pulled up the accelerator pedal. This entire ordeal was shocking and an unbelievable narrow escape from a major catastrophic event. I thanked god & called 911 and the highway patrol police came to the spot and promptly helped to move the vehicle and myself from the freeway traffic. The 2010 toyota prius was moved to toyota dealer service center where I purchased the car & performed every scheduled maintenance service punctually. Incidentally the last service and certification was in 12/2013. It is obvious that even regular dealer maintenance service and certification did not help this vehicle. Report filed with toyota motor customer service.

Filed Sep 20, 2012 · Acceleration, Brakes · 20,100 miles · KY · crash

Traveling on parkway when we were approaching a vehicle going south down at approximately 55 we were traveling 72 with cruise control engaged, I tapped the brakes to try and slow and nothing happened I then held the brake pedal down for more than 15 seconds with no success, tried to disengage the cruise by pulling back on the handle on the steering wheel and still it would not disengage, we struck the truck at 72 MPH only because we had no where else to go and the vehicle would not disengage cruise. The cruise control light was still illuminated after the vehicle came to rest after impact and the vehicle brakes still did not appear to function, this vehicle was a toyota lease and was told multiple times by toyota that the issues was recalled by toyota and that this vehicle had the recall performed.

Filed Feb 18, 2012 · Acceleration · 10 miles · TN

The dynamic radar cruise control system suddenly applies brakes while, or soon after, passing a large truck (18 wheeler). Happens rarely. But when it does happen, it is always while, or soon after, slowly passing a larger truck on an interstate and traveling about 70 MPH. When it does occur, it normally occurs when the front of the prius is slightly behind the front of the truck (in the immediate lane to my right) where the truck should be outside the range of the radar. The last time, though, the prius was well in front of the truck, there was no vehicle in front of me. And, yes, there was no dirt, snow, etc. On the front of the car that might affect the operation of the radar.

Filed Aug 23, 2011 · Acceleration · 10,000 miles · NY

Tl* the contact owns a 2010 toyota prius. The contact stated that while driving at various speeds, the adaptive cruise control feature would unexpectedly malfunction and force the brakes to engage. The contact stated that if the vehicle traveling in front of him were to turn to the left or right, his brakes would suddenly engage. The vehicle was taken to an authorized dealer, where the contact was informed that the vehicle was operating to specifications. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was 10,000.

Filed Aug 1, 2011 · Acceleration · 18,250 miles · MN

Tl* the contact owns a 2010 toyota prius. While driving approximately 71 MPH with the cruise control activated the vehicle began to accelerate and decelerate on its own. The cruise control light illuminated and began to flash on the instrument panel erratically. The vehicle had a dynamic radar cruise control feature which recognized when there was a vehicle in close proximity and was also illuminated; however, there was not a vehicle within close proximity. The contact depressed the brake pedal but the vehicle would not stop until the cruise control was manually deactivated. The contact had not used the cruise control feature since the failure occurred. The vehicle was not taken to the dealer for diagnostic testing. The vehicle was not repaired. The approximate failure mileage was 18,250. Updated 09/28/11*lj updated 2/21/12

Filed May 4, 2011 · MD

2010 toyota prius. Consumer writes in regards to rapid acceleration issues *tgw the consumer wants to know did the investigation into this matter examine the interrelationship between the accelerator, braking system and cruise control.

Filed Apr 5, 2011 · Acceleration · 5,000 miles · HI

2010 prius 4 dr hatchback the speed control on my prius uses radar to speed up and slow down. If I come up on a car doing 45 MPH and I'm at 55, the vehicle slows down. When I turn to the other traffic lane, and the lane is clear the car accelerates rapidly. On a number of occasions I have braked to disengage the cruise control, I fell like I don't have control of the car. The fix: adjust the computer so speed acceleration is slower. I think it is a crash hazard.