2014 Toyota Prius Forward collision avoidance Problems
- Complaints
- 6about this part
- Share
- 3%of 210 total for the year
- Median mileage
- —not reported
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 6 complaints about the forward collision avoidance of the 2014 Toyota Prius, 3% of the 210 complaints for this model year. 1 of these say a crash was involved, according to the filers.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“The traction control, abs, and emergency brake light came on. We checked and the code produced was C1391. There’s a humming noise every 10 or so seconds when idle. The humming noise is also present when braking. We did some research and this appears to be an issue with Toyota Prius. We called the dealership and were informed that this was not a known issue. Thank you.”
NHTSA complaint #11748069, filed 2026-07“Code C1391 - Abnormal Leak in Accumulator. Accumulator for the brake pump is not holding pressure so the pump has to keep turning on to refill. Brake pump and ABS unit have to be replaced. In emergency situations, a malfunctioning ABS module leads to increased stopping distances and loss of steering control during hard braking. Lastly, tires can be worn more easily, which could lead to tire blowouts. This puts myself and others at risk for deadly consequences due to an increased chance for collision if I am unable to control or stop my car. …”
NHTSA complaint #11576465, filed 2024-03“The Toyota Prius, models through 2010 - 2015 have a known issue with the Brake Booster (actuator) and ABS Pump where the parts will degrade and break at or around 100,000mi. Toyota issued a bulletin and had a replacement program that covered the part that has since elapsed but has not corrected the issue with existing stock and inventory so the problem remains. When I purchased my car I was the 2nd owner, the car was purchased with roughly 160,000mi. The previous owner had informed me that he already replaced the actuator and ABS pump so I wouldn't have to worry about that repair. …”
NHTSA complaint #11772582, filed 2026-10“ABS, traction control, brake system, and brake lights turned on while driving. Took the car to the mechanic and pulled the code C1391. It seems from other complaints to NHTSA that it is a common issue and quite dangerous, meaning the brake system is failing.”
NHTSA complaint #11741205, filed 2026-06“The brake system malfunctioned suddenly. While driving and while stopped, the brake pedal became very hard and braking behavior became unpredictable. The vehicle sometimes brakes aggressively and other times requires excessive pedal force to stop. The ABS and BRAKE warning lights illuminated. The vehicle no longer provides normal braking assistance. This issue is related to a failure of the brake actuator / brake booster, which is a known issue affecting Toyota Prius models from 2010 to 2015. …”
NHTSA complaint #11707101, filed 2025-12Related service bulletins
- 10203533Oct 4, 2021TSB: For proper calibration of the millimeter wave radar sensor, the vehicle and radar target must be on a level surface with a consistent plane. If a level surface with a…
Forward collision avoidance: other model years
| Year | Complaints | Share of year |
|---|---|---|
| 2025 | 3 | 19% |
| 2023 | 1 | 5% |
| 2021 | 1 | 17% |
| 2020 | 1 | 7% |
| 2019 | 4 | 13% |
| 2018 | 1 | 3% |
| 2017 | 1 | 1% |
| 2016 | 2 | 1% |
| 2015 | 7 | 4% |
| 2014 | 6 | 3% |
| 2013 | 12 | 3% |
| 2012 | 3 | 1% |
| 2011 | 5 | 1% |
| 2010 | 18 | 1% |
| 2009 | 5 | 1% |
| 2008 | 3 | 0% |
| 2007 | 1 | 0% |
| 2006 | 1 | 0% |
| 2004 | 1 | 0% |
Other parts of the 2014 Toyota Prius
103 complaintsElectrical system
33 complaintsOther or unknown
27 complaintsEngine
17 complaintsAir bags
14 complaintsVehicle speed control
14 complaintsVisibility (wipers, defrost, mirrors)
12 complaintsBody and structure
9 complaintsElectronic stability control
8 complaintsSteering
8 complaintsExterior lighting
6 complaintsTransmission and drivetrain
6 complaints
← All problems reported for the 2014 Toyota Prius
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 30, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology