KNOWN FAULTS · Toyota

Toyota Prius (III) common problems.

2009–2015 · Hybrid / Plug-in hybrid

Sources are not verified in real time and no entry confirms that your car is affected.

5 known faults with sources

Engines: 1.8 Hybrid (Hybrid) · Prius Plug-in (Plug-in hybrid)

Applies if: Toyota USA tech tip for all its models: it applies if the judder began after wheels, pads or discs were removed or changed.

Brake judder from wheel nuts over-tightened or tightened unevenly (Toyota tech tip)Brakes

Engine / equipment: Any Toyota: it depends on how the wheels are tightened
Period mentioned: 2016 tech tip for all its models
Symptoms: Vibration in the steering wheel and the pedal when braking, even gently and at any speed, often shortly after wheels, pads or discs were changed.
Possible cause described: Toyota points out in a tech tip that if the wheel nuts are over-tightened or tightened unevenly (a single one is enough), the brake disc is left with runout and brake judder appears. It happens above all when they are run fully home with an impact gun instead of a torque wrench in a star pattern.
Check for the garage: Ask the garage to loosen and re-tighten the nuts with a torque wrench, to the manual's torque and in a star pattern, and to measure whether the discs have been left warped; if so, they will need skimming or replacing.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Engines: 1.8 Hybrid (Hybrid) · Prius Plug-in (Plug-in hybrid)

Applies if: The Prius Plug-in uses the same 1.8 hybrid engine (2ZR-FXE).

Clogged EGR and head gasket on the 1.8 hybrid (2ZR-FXE)Engine

Engine / equipment: 1.8 hybrid (2ZR-FXE): Prius III, Prius+ and Auris hybrid
Period mentioned: Approx. 2010–2015
Symptoms: Knocking or rattling on cold start, misfires (P0301–P0304), coolant loss and, eventually, a damaged head gasket.
Possible cause described: The EGR cooler and passages clog with soot; uneven gas distribution causes knock and misfires that end up damaging the head gasket. Toyota issued a technical bulletin (T-SB-0116-15) for the 2010–2015 Prius.
Check for the garage: Read the misfire codes, watch the coolant level and clean the EGR cooler, valve and manifold preventively; if coolant is lost with no visible leak, run a combustion-gas test.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Engines: 1.8 Hybrid (Hybrid) · Prius Plug-in (Plug-in hybrid)

Clogged hybrid battery cooling fan and filterHigh-voltage battery

Engine / equipment: Hybrid battery cooled with cabin air (intake next to the rear seat): Prius, Yaris, Auris, Corolla, C-HR, RAV4, Camry and others
Period mentioned: 2003 onwards
Symptoms: Hybrid battery cooling maintenance message, warning light with codes P0A80 or P0A7F, a noisy fan and less electric assistance; if ignored, the battery ages faster.
Possible cause described: Dust, pet hair or dirt block the filter and fan that cool the battery; so do objects covering the intake. Toyota USA issued bulletin T-SB-0074-20 (2003–2020 Prius and Camry, Corolla, Highlander, RAV4 and Mirai hybrids up to 2020) and recommends cleaning the filter every 5,000 miles (about 8,000 km).
Check for the garage: Clean or replace the filter and clean the fan before condemning the battery; keep the intake grille clear. At the garage, read the codes and, if needed, install the software Toyota specifies.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Engines: 1.8 Hybrid (Hybrid) · Prius Plug-in (Plug-in hybrid)

Applies if: Weak points of this model from inspections, breakdown statistics and recalls; anything specific to one engine is stated in the sheet.

Applies if: The Plug-in shares body and engine with the Prius III, but the guide does not cover it separately: confirm by VIN.

Curtain airbag, rusty discs and battery on the Prius IIIKnown weak points

Engine / equipment: Toyota Prius III (ZVW30 / ZVW35)
Period mentioned: 2009–2016
Symptoms: Rusty brake discs (little used because of regenerative braking), shock absorbers worn from about 200,000 km, a high-voltage battery that discharges (isolated cases in 2010 and 2011) and squeaks and easily scratched interior plastics.
Possible cause described: Cracks in a weld of the curtain airbag’s gas generator (built 2010–2012) could fire it for no reason and throw out parts: worldwide recall. Battery discharge can only be fixed by a Toyota garage.
Check for the garage: Check the airbag recall by VIN; brake hard now and then to clean the discs and check them at every service; have the hybrid battery’s condition checked.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.

Engines: 1.8 Hybrid (Hybrid)

Prius inverter coolant pumpElectric drive

Engine / equipment: Hybrid inverter cooling circuit
Period mentioned: 2003–2015
Symptoms: Hybrid-system warning, a fan that keeps running with the car off and a risk of the inverter overheating.
Possible cause described: The electric pump of the inverter circuit can fail; without circulation, the inverter and transmission overheat. Using a coolant other than specified can clog the passages.
Check for the garage: Check the inverter reservoir level and whether the coolant circulates, read the codes and test the pump before condemning the inverter; ask Toyota about campaigns for the VIN.
Cost cited in the source: No verified estimate; ask the garage for a quote.A rough figure from the original database, not an up-to-date quote.