2020 Subaru Forester: lane keeping assist jerks the wheel

Filed May 19, 2024 · Driver assistance, Engine · OH

2020 subaru forester just had a check engine light appear. The engine malfunction code is p26a3, which is a defective thermostatic control valve. This malfunction also affects the vehicle manufacturers advanced driver assitance systems such as: "eyesight" blind spot monitoring, lane keep assist, etc. Vehicle only has 51,000 miles on it.

Filed Apr 27, 2024 · Driver assistance, Engine · UT

I was driving to work and many of my warning lights suddenly came on. This includes my check engine light, my lane assist light, my auto collision braking, my eye sight disabled and my cool engine light keeps going on and off. My cabin heating also isn’t working. There is no reason for this happening other than my thermo control valve failing.

Filed Mar 20, 2024 · Transmission · WA

The thermo control valve failed causing the coolant to run at full and not allowing the engine to reach proper temperature and the heating system to not provide heat, also it caused multiple safety systems to turn off including eye sight, emergency braking, rear auto brake, lane keeping, adaptive cruise control, traction control. the failure of this unit is a known issue to Subaru per their own service bulletin 09-80-21, while mine was not covered by Subaru's own warranty due to the mileage this vehicle is less than 5 years old, the repair costs will be $2000.00+ as quoted by the dealer.

Filed Mar 8, 2024 · Driver assistance, Engine · MN

On Sunday, [XXX] we were traveling in our 2020 Subaru Forester on a trip from Minnesota to Florida for a vacation. Not long into cross country trip we found ourselves stranded on the side of the highway uncertain about the ability of our vehicle to continue to due to a defective Thermo Control Valve failure. About 200 miles into our trip, while driving at highway speeds south of Rochester, MN the dashboard lit up. The check engine light was on, and other safety features were lit up on the dash as disabled (Eye-sight technology, lane assist, automatic vehicle collision braking). The heat would not work after this incident. We checked the owners manual, and then drove to an Auto-parts store to have a scan done to determine the error code. The code "P26A3 - Engine coolant bypass valve A Range/Performance" was indicated. In checking online we discovered that a Thermo Control Valve replacement was needed ASAP and to continue driving the vehicle could risk severe engine damage. Since it was a Sunday, and we were essentially stranded if we couldn't use the vehicle. We continued on, stopping and checking the engine periodically for overheating. We were able to get an appointment at Lou Fusz Subaru in St. Peters, MO on Monday afternoon and they replaced the Thermo Control Valve at a cost of $1,961.51. We were told that this wasn't under warranty due to the mileage on the vehicle (76,358 miles). In researching this issue online, we found that the Thermo Control Valve failure to be a common issue and certain year/model vehicles and Subaru should have recalled this part a long time ago (in our opinion). INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Feb 8, 2024 · Driver assistance, Engine · CA

The thermal control valve stopped working. The car has <50K miles on it. The error also results in many/all of the safety systems being deactivated (no adaptive cruise control, no lane centering, no rear braking, etc.)

Filed Jan 29, 2024 · Airbags, Electrical · TX

I started the car to make a trip to town to run some errands. When I cranked the engine the Check Engine light came on. The S for Sport Mode was flashing and a No Eyesight warning came on. Also SRS Side Airbag light came on to indicate it was not working. And another light came on showing a car going out of its lane, but I don't know if it was the Lane Keep Assist light or not.

Filed Jan 15, 2024 · Driver assistance, Transmission · CA

While accelerating to merge in the freeway the Thermo Control Valve malfunctioned, causing check engine light to come on which turned off all the safety features (lane assist off, precollision off, RAB and eyesight off) of my Subaru 2020 Forester Sport. I’ve researched the internet and shows it is a common issue. I brought it to a subaru dealership and was told it is not safe to drive the vehicle. Since I just passed 60k powertrain warranty (around 62k), it is not covered and had to pay over $3,000.

Filed Dec 1, 2023 · Driver assistance, Engine · PA

Check engine light came on, low temp light stays on, Eyesight disabled, lane departure, emergency breaking, etc have all been disabled due to the issue. I took it to the local autobody shop and they found code p0128 | Coolant Thermostat Issue. This has caused all safety features to become disabled as mentioned above. I was told by the local shop that I need to go to the dealership. I have not brought it to the dealership yet however, after looking online I found that this is a common issue with this make and model vehicle however, nothing has been done by Subaru to recall the component. I am going to bring the car to a dealership however, I'm upset that Subaru hasn't acted on the information that they have a faulty component in this vehicle. I am very concerned with cost of repairs since I am being forced to go to the dealer.

Filed Nov 30, 2023 · Transmission · VA

The Thermo Control Valve failed at 33,945 miles. Because of this, the heater, Eye Sight, Cruise Control, Lane Assist, and Collision Brake did not work. The engine was then only running at "Sport" mode. It did not regulate the heat to the oil and could've caused sludge. The problem was confirmed by a Subaru Dealer Service Shop. I only noticed this problem when the blue thermometer light came on the dash board. Usually I wait about 5 min and once the car is warmed up the light goes away. This time the blue thermometer warning light did not turn off and stayed on for the remainder of the trip. When the car was restarted on the same day the engine check light came on. Eye Sight, Lane assist and Collision assist lights were on.

Filed Nov 8, 2023 · Brakes, Electrical · NY

The thermo control valve malfunctioned causing the check engine light to come on which shut down all the safety features in the vehicle including the front eye sight camera, blind spot warning, the rear automatic braking, lane departure warning, adaptive cruise control, and lane keeping assistance.

Filed Sep 19, 2023 · Driver assistance, Engine · GA

The thermo control valve malfunctioned causing the check engine light to come on which shut down all the safety features in the vehicle including the front eye sight camera, blind spot warning, the rear automatic braking, lane departure warning, adaptive cruise control, and lane keeping assistance. The check engine computer readout diagnostic trouble code was P26A5 "Engine Coolant Bypass Valve "A" Position Sensor Circuit Range/Performance". The vehicle was taken to a Subaru dealer who found the thermo valve performance was out of spec. This vehicle has not been recalled although the manufacturer replaced the part in 2021 vehicles acknowledging the valve was faulty. Because of the mileage on my vehicle, it was not covered under the warranty although many have been replaced under the manufacturer's warranty due to the failure of this valve under the 60,000 mile warranty. I believe this should be a recall item for others who experience this issue.

Filed Aug 30, 2023 · Transmission · MO

The thermo control valve malfunctioned causing the check engine light to come on which shut down all the safety features in the vehicle including the front eye sight camera, blind spot warning, the rear automatic braking, lane departure warning, adaptive cruise control, and lane keeping assistance. The check engine computer readout diagnostic trouble code was P26A5 "Engine Coolant Bypass Valve "A" Position Sensor Circuit Range/Performance". The vehicle was taken to a Subaru dealer who found the thermo valve performance was out of spec. The valve was replaced. This vehicle has not been recalled although the manufacturer replaced the part in 2021 vehicles acknowledging the valve was faulty. Because of the mileage on my vehicle, it was not covered under the warranty although many have been replaced under the manufacturer's warranty due to the failure of this valve under the 60,000 mile warranty. Through a "Goodwill gesture" Subaru replaced the part in my car at no cost. I believe this should be a recall item for others who experience this issue.