2018 Toyota Yaris Problems: 8 Known Issues

On the 2007-2018 Toyota Yaris, the Yaris's electric power steering system can fail, causing sudden loss of power assist and very heavy steering. The EPS motor or its control module malfunctions, typically with a power steering warning light. The failure is sudden and dangerous at low speeds.

On the 2007-2018 Toyota Yaris, the U340E/U441E 4-speed automatic in the Yaris develops shudder during torque converter lockup and harsh shifts, particularly 1-2 and 2-3 shifts. Worn transmission fluid and torque converter clutch material are the primary causes.

On the 2016-2020 Toyota Yaris Skyactiv-G 1.5L, the Mazda-sourced 6-speed automatic in the 2016-2018 Yaris iA and 2019-2020 Yaris sedan (a completely different unit from the Toyota U340E 4-speed in the hatchback) draws consistent owner complaints of a whistling or whining noise during the 1-2 and 2-3 upshifts, plus a grinding or clunking noise when selecting Drive from Park. Reports range from a noise-only nuisance to units replaced under warranty, and a few owners describe progression to gear slippage and a stall with audible metal-on-metal. Because this transmission uses a very small lock-up-early torque converter for economy, converter shudder and fluid degradation show up earlier than owners expect for a Toyota-badged car.

On the 2007-2018 Toyota Yaris, the 1NZ-FE/2NZ-FE coil-on-plug packs are a recurring failure point, and cylinder 1 - the one closest to the front of the engine and nearest the cowl drain area - fails disproportionately. Two mechanisms show up on the forums: the coil's internal windings break down with heat and age, and water gets down the plug tube (from a leaking valve cover gasket, a clogged cowl drain, or an engine bay wash) and sits on the coil boot, shorting the spark to ground. Owners describe replacing the plug and coil, getting a clean year, then having it recur if the water path was never fixed. A dying coil that is left alone dumps raw fuel into the catalyst and can eventually kill the converter.

On the 2007-2018 Toyota Yaris 1.5L 1NZ-FE I4, the Yaris front engine mount (also called the dogbone mount or torque strut) fails prematurely, typically between 60,000-100,000 miles. The rubber deteriorates and the mount collapses, allowing excessive engine movement during acceleration and braking. This causes a harsh clunk when shifting from Park to Drive or Reverse, vibrations at idle, and can stress the CV axles and transmission mounts.

On the 2016-2020 Toyota Yaris Skyactiv-G 1.5L, the 2016 Scion iA / 2017-2018 Yaris iA and the 2019-2020 Yaris sedan are rebadged Mazda2s and carry Mazda's Connect head unit, not a Toyota system - so this failure does not exist on the Toyota-built XP130 hatchback. Owners report the display going black and the unit entering an endless crash-and-reboot cycle, sometimes triggered by a specific USB device or by switching between a Bluetooth call and a streaming audio app. The reverse camera image also fails to appear or freezes, which matters because it is the federally required backing image. The root cause on the Mazda side is head unit firmware, aggravated by non-compliant USB cables/drives drawing on the port.

On the 2007-2018 Toyota Yaris, a very common Yaris electrical fault: the rear wheel speed sensor is integrated into the rear hub/bearing assembly and is not sold separately. The weather seal where the harness plugs into the hub has a gap, so road spray and winter salt wick into the connector, corrode the pins and degrade the signal. The ABS light and the red brake/'!' light come on together, often intermittently at first and worse in wet or winter weather. Dealers routinely quote a complete rear hub assembly (owners report $650-750 CAD per side) when the actual fault is frequently just a dirty, corroded connector.

On the 2007-2019 Toyota Yaris, the Yaris has been named in seven separate NHTSA campaigns on tire and loading information. Six concern the load carrying capacity modification (addendum) label and one concerns the spare tire's inflation. The addendum label is a separate label on the driver's side center pillar, next to the Tire and Loading Information placard. FMVSS 110 requires it when accessories above a set weight are added between factory certification and first retail sale, and it states how much those accessories reduce the vehicle's load carrying capacity. When the addendum label is missing, wrong or unreadable, a driver can overload the car without knowing it, which degrades braking, handling and tire load margin and increases crash risk. The campaigns: 09V223 (Toyota; accessories fitted at Toyota vehicle processing centers; first filed for 1,348 vehicles built from 2 June 2008, then expanded to 27,080 vehicles built 1 September 2005 to 4 May 2009, including 2007-2009 Yaris sedan and hatchback); 10V035 (Gulf States Toyota, 2008-2010 Yaris) and 10V036 (Southeast Toyota, 2007-2010 Yaris), both for vehicles sold without the required addendum label; 16V236 (Southeast Toyota, 2016, label does not reflect the weight of installed accessories); 17V295 (Gulf States Toyota, 2017: the spare tire was not inflated to the pressure stated on the Tire Pressure Label); 19V244 (Gulf States Toyota, 2019, label text may become illegible); and 19V503 (Southeast Toyota, 2017-2019 Yaris iA with factory-installed floor mats, label incorrect). Most are distributor campaigns, so they apply only to cars that passed through those distributors or processing centers.