A week after my routine oil changed at 31K, the check engine light along with flashing "s" pop up. The next day the check engine disappeared. I was some what happy and continue to drive car as normal for 2 days, then check engine light came back again and this time is staying for good. I just can't believed that 4 years old car is having this issue. I've owned so many cars prior to this 2020 Subaru Forester, never once that those cars have problems like this one. I feel that i'm at risk driving without no eyesight or collision prevention warning.. when the check engine comes on, those two things are disable. After a long research and reading about so many people with same issues, i feel that they should be a recalling to fix the thermal valve control.
2020 Subaru Forester driver assistance complaints
Page 2 of 3: complaints 11 to 40 of 59, newest first, as owners wrote them.
Eyesight pre-collision braking feature and pre-collision throttle management feature malfunctioned and caused the 2020 Forester to accelerate unexpectedly and lurch forward while I was manually braking and slowing to come to a complete stop behind two other vehicles stopped at a steady red light. See class action lawsuit Weston, et al. v. Subaru of America, Inc., et al. In US District Court Case No. [XXX] which alleges that the vehicle contains certain defects that caused sudden and unintended acceleration without driver input; acceleration while manually braking; and that these defects created a safety risk, because they severely affected the driver's ability to control the car's speed, acceleration, and deceleration, and increase the risk of a collision, which did in fact occur. The defective car was completely totaled and towed to a salvage yard by the police and the insurance company. Defect malfunction caused a collision which resulted in property damage and personal injury to three vehicles and three people. I mentioned the defect to my insurance company at the time of the accident. I do not know if they chose to follow up and inspect the vehicle. The problem occurred twice before ( not resulting in property damage or injury) and I took it to my Subaru dealer both times and they claim that they could not find anything wrong, but oddly did not note that they checked for the problem which I brought to their attention on the written summary/invoice for my service visit. See the class action lawsuit- this is apparently the typical dealer non-response to the problem. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Within one month the same thing happened. I turn on the car and the eyesight warning light is on (eyesight feature disabled), flashing "S" drive is on, "break" light is on, and check engine light is on. Due to this cruise control isn't working. My plan was to take it to a mechanic/dealership that Monday. By Monday morning, after about 15 minutes of driving, all warning signs disappeared. This exact thing happened a few weeks later (this morning). I started googling issues and seems like this is an issue for many customers and is just a malfunctioning Thermo Control Valve, no actual problem. What do I do about this? This is much less important - but also seems like a quality issue, at drivers side, the seat cover is starting to crack, looking like this is car is over 10 years old, we've had it for less than 4 years and this shouldn't be happening on a car of this caliber. Photos attached
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.
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.
Multiple dashboard lights are on including starlink, eyesight, check engine, thermostat, and a blinking s. A quick Google search shows that this exact combination is a known issue. Safety concern is that all the accident prevention systems are down leaving me at risk.
While driving temperature light, check engine light, all ADAS lights came on as inoperable (cameras, warning, ABS, BSD/RCTA), no heat (including defrost) available to defrost or for cabin. Appointment 3/13 replaced thermo control valve assembly , coolant bypass valve, intake gaskets, fuel line, coolant, total charges $2070. Luckily had extended warranty I bought, that I had to make a claim on. Dangerous to drive (no camera based safety features available, no defrost for the snowy weather, no emergency braking or other collision safety features on, this affected the entire 'eyesight' system). The engine also had no thermo control regulation during this time, affecting not just then, but possible future performance and early aging due to disregulation.
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)
1-16-24:car wouldn’t open and start; jump-started by AAA to dealer; dealer kept overnight & checked battery: said charge held, ready to go home. 1-30-24, 4 pm-ish: able to start n drive, but check engine& eyesight warning light came on- late in day, so didn’t drive to dealer. 1-31-24: car dead; jump-started by AAA again & drove to dealer. On 2-1-24, dealer sends a video & says replaced battery, but check engine light & eye sight warning light still on; investigated further & found there was a lot of water that had pooled under the passenger seat & caused some corrosion- I.e.: shorted out electrical system. I asked dealer to report to Subaru since this seemed like a car defect. 2-9-24- dealer says Subaru won’t repair it at their expense and it’s a 25 hour job & will cost a lot. Dealer wanted me to file a claim with my insurance, but car was not driven through rain, high water, or stored in a flooded garage or on a flooded street. The water in the car seems like a design defect on the part of Subaru.
Started engine after parking and check engine light came on, eyesight disabled, and flashing “s”. Stopped driving and took vehicle to dealer. Diagnosed as thermo control unit. Told they didn’t have a loaner and was safe to drive for a few days. Has no heat and engine would not warm up. No safety systems. Retained 3 days later to dealer when loaner was available. Repaired under powertrain warranty.
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.)
The contact owns a 2020 Subaru Forester. The contact stated while driving 75 MPH, the Forward Collision Avoidance Automatic Emergency Braking system activated and applied the brakes. The contact was able to pull to the shoulder of the roadway, where he smelled a burnt smell in the interior of the vehicle. The vehicle returned to normal functionality, but the failure became a regular occurrence. The check engine and brake warning lights were illuminated. The vehicle was taken to the dealer, who diagnosed a failure with the throttle body. The vehicle was repaired, but the failure reoccurred. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 35,600.
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.
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.
41k miles P26A3 P26A5 ****Eyesight disabled*** ***Forward collision disabled *** Failed TCV and dealer will not cover because warranty period is over.
While driving, most of the dash errors lights lit up- alerting me that the Eyesight Warning, RAB ( Reverse Auto Braking) and other safety functions were disabled. The Check Engine light was on and a flashing S next to it. Cold Engine light was illuminated as well. Dealer diagnosed with a faulty Thermal Control Valve, which somehow disabled all safety features. This is a common failure of Subarus and a recall is needed.
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.
The car dies when it stops for a traffic stop. Sometimes it starts again and and sometimes it does not. It does not do it when the air is on. People honk at you in traffic if you do not start right away. I thought there was a recall on Subarus for same which is why I never bought one. The vehicle has been inspected. It also unlocks itself sometimes after I lock it.
While I was traveling I stopped at a rest area and when I restarted my car, my panel lit up like a Christmas tree. All my safety assist systems were disabled and my check engine light came on. When I got home I had my mechanic run the codes and it came back to the thermo control valve. This happened on 8-29-2023. I researched the problem and Subaru put out a service bulletin in February 2022 but never notified me. My car is out of warranty now and am forced to drive without my safety systems because, 1- they don’t carry the part in stock and 2- the cost to repair is over $1400.00. Subaru was aware of the problem but kept it quiet. I feel this is a scam and Subaru should recall this part. I was warned that my car could die at any time. I bought it for those very safety systems as I am a senior citizen and rely on them now.
While driving, the 2020 Forester, the check engine light, collision light, eyesight function lights all went on at the same time. I brought vehicle to check diagnostics and it is showing Engine Coolant Bypass Valve "A" Control Circuit low in Power Train System. Their were no messages prior to all the lights turning on and I was able to bring into the dealer for oil change but not able to make an appointment for repair for a few days from now
Error code (P26A3?)for - Engine Coolant Bypass Valve. Causes the "Check Engine" light to come on and automatically disables ALL of the safety and collision mitigation systems. The Engine Coolant Bypass Valve failure is common and a known issue and Subaru has already updated the part on newer vehicle models. The common failure of the coolant bypass valve should not be disabling the safety features and the collision avoidance systems.
I was driving on a paved two lane rural route and hit a small bump in the road. Immediately, my check engine light came on and all the safety features turned off. Control panel showed multiple safety features off and the Sport mode indicator light blinking. My car only has 17K miles on it and I have had it just over a month. I was able to drive it safely home and when I called the dealership the next morning I was told I could continue to drive it until the service appointment six days later. When I got home, my husband checked it with his CEL reader and got the code for the temperature control valve (an issue known by Subaru). This was confirmed by the dealership and I was told after having driven it for several days that it should not be driven. The repair is being covered under the power train warranty.
The thermo control valve on my 2020 Subaru Forester is broken and needs to be replaced. I have owned the car for 2 years, am the first owner, and it has less than 19,000 miles. 90 minutes into a drive the "coolant temp low" indicator light came on. After I pulled over, turned off the engine, and turned it back on the check engine light and sport mode indicator light came on, and all ADAS were disabled. The coolant level was low so I refilled it and took it to the manufacturer the next morning. They inspected my car and confirmed it the thermo control valve was broken. It is still broken as I cannot afford the repair and it is available for inspection upon request. My safety was put at risk by not having access to the ADAS forward collision warning, emergency breaking, and lane departure.
The check engine light illuminated and the thermo control valve failed at 3 years old. The defrost and heater stopped working immediately making visibility extremely difficult . The eyesight and automatic braking system were also disabled due to the TCV issue. My Forester mpg dropped to under 20 mpg. The Subaru dealer inspected and confirmed code P26A3 and stated the thermo control valve needs to be replaced.
Was slowly pulling into a parking spot when the "Automatic Emergency Braking" and "Collision Avoidance Systems" engaged. The systems said that there was an "object detected" and slammed the car to a stop. Shut off the car and got out, there was no object. Had to disable the AEB system to pull into the parking space. Vehicle and component have not been inspected for this issue. Vehicle received regular maintenance at a shop (oil change) about 1 month ago and new tires about 1 week ago. Problem has not been confirmed.
Car stalls occasionally while stopped in traffic, at a signal, stop sign, and in heavy street or highway traffic. I have read about this, and it is problematic for this make and model, posing a significant safety hazard.
Thermo control valve stays open. Needs replacement. Automatic brakes have gone on with no car in front of vehicle. Unsafe.
When I was driving this car one night, every dash light was suddenly activated and remained on -- and as a result all safety features were deactivated. When I was able to do so, I touched the battery cables together to reboot the system. I had to do this 3 times over the course of 4 days. Realizing the problem was chronic, I took the car to the dealership (a 2 hour drive), where a service tech explained the problem 'was caused by a low battery.' This car is only 2 years old. A new car battery should last longer than 2 years. It thus seems to me the battery was defective or the car improperly drained it somehow. More important, there is no warning that a 'low battery' -- one which can easily start a car -- could still deactivate safety features while driving.
This is about a problem of which your agency is already aware. Subaru of America has been aware of a defective Thermo Control Valve for almost a year (Part 21319AA010). The part was redesigned since the initial part was subject to extreme corrosion. The redesigned part has the same part number as the original part. Subaru did not do any recall but instead waited for the parts to fail. When it fails on a car with safety features (called "eyesight"), each and every safety feature is permanently disabled until the redesigned part is installed. In addition, the engine runs too cool and there is little or no cabin heat. My car has been on the lot of my local dealership for 2 months with no end in sight. My car is covered by the original warranty and an extended warranty. Managers at the dealership have told me that they have no idea when the part will arrive, that it may be many months and that there are many people already waiting for the part. A 6-page letter by me to the General Counsel of Subaru of America did not result in any direct response. By information and belief, this involves thousands of cars nationwide. By information and belief, dealerships are initially telling people the cars are still drivable despite the loss of all safety features since this what was initially told to me. I refused to accept the car in a defective unsafe condition. There may be thousands of cars being driven in which said safety features are fully disabled. Subaru claims the part has been on "back order" since March. By information and belief, based upon Subaru's own February 2022 service bulletin, it appears that the newly designed part is currently being installed on new cars at the factory thereby putting into question the "backorder" label. This analysis was enunciated in detail in my letter to Subaru of America's General Counsel and there was no response contesting that allegation. Your agency's investigation and intervention are immediately required.
Corrupted Driver Assist Software. Dashboard icons for hands on steering wheel, dynamic vehicle control, lane change control were flashing that systems were off, controls were turned off randomly. Vehicle was not tracking appropriately in its lane, steering was not acting correctly. Car at times acted as if it were being blown by a strong crosswind. Steering between lanes was not consistent. Icon warning that my hands were not on steering wheel when both my hands were on the steering wheel.
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