2021 TOYOTA HIGHLANDER Unknown Or Other Problems

I am reporting a serious safety defect involving the rear brake system of my 2021 Toyota Highlander, purchased from Penn Toyota (Glen Cove, NY). The dealership represented the vehicle as “Toyota Certified” and indicated that it passed all safety inspections. On November 15, 2025, I discovered that the rear brake rotors and pads were in extremely unsafe condition, showing severe corrosion, deep pitting, uneven pad wear, and structural deterioration. This damage clearly developed over a long period of time and indicates that the vehicle could not have passed a legitimate safety inspection at the time of sale. The rear brakes had to be replaced immediately to prevent potential brake failure. After replacing the rear rotors and pads, the vehicle passed the New York State Inspection on the same day, proving that the previous brake condition was unsafe and improperly inspected. This raises concerns of: Brake safety failure Improper or falsified dealership inspection Risk of reduced stopping power Potential loss of vehicle control I am submitting photos, the repair invoice, and the inspection result that confirmed the brakes were unsafe prior to repair.

Started with a transmission whining. Now is setting check engine light and jerking. Toyota knows there is a manufacturing defect in the UA80 transmission in these vehicles, but continued to sell them even after the released TSB# T-SB-0008-21, and refuses to repair this under warranty. Toyota is the only company offering replacement transmissions and therefore can set there own price to scam consumers. Please help us get a resolution.

The rear hatch of the vehicle started malfunctioning right when the three year manufacture's warranty was expiring on 08/2024 (very convenient). It would only open part way, barely or sometimes not open at all. One instance, my dog's tail got stuck in the hatch and it would not open. I had to force it open and thankfully I am able to do that. January of 2025 I took the car into Will's Toyota in Twin Falls, ID (where I purchased it new) and they told me that my option was to replace the hydraulic struts that were $1000 for the service. I took the car in on 10/23/25 due to the issue getting worse to have them replace the hydraulic struts. The dealership said they've had a lot of cars with the same issue. I just do not understand how a company can sell a car and a major part of the car fail conveniently when the warranty is to expire. Oh and I called Toyota customer service to complain and they said they don't keep track of this kind of thing...

During rain, the A-pillar and headliner show evidence of a leak. Open source research found this is likely due to faulty or poor quality components used in the roof rail system. My vehicle is completely stock with no additions or installations on the roof, just the factory rails.

Glass in sunroof exploded, loudly, while driving on interstate, at 65 miles an hour, showering passenger and driver in shards of glass. There was no impact to the sunroof. Just a loud explosion. Heavy traffic at high speed while covered in glass had to make emergency stop. Glass could have easily gotten in our eyes. Thank goodness the two of us were wearing a ball cap and a visor. Would gladly have car available for inspection upon request. We will take pictures.

Transmission. I believe the transmission is defective. A lot of customers has complained that toyota Highlander 2021 transmission is defective I was driving my car and the transmission went bad, I could not move my car again. I had to tow it to a mechanic and they diagnose that the transmission is bad

My car has been making a grinding and whining noise. I took it to the dealership and the service manager stated Toyota has been having a known issue on transmission and it will have to be replaced. The vehicle can stop working while i am driving and cause a very bad accident.

The sunroof glass on our 2021 Highlander unexplainably shattered on our ride home on 7/20/25 at approximately 12:30PM. Sky was overcast, and the temperature was in the mid 80's. We had just entered the highway and were still accelerating to highway speed. We were not near a pedestrian overpass where a rock could have been tossed from above. Broken glass edges are pointing upward. The sunroof was in the fully closed position and not tilted. Safety would have been at extreme risk if we did not have the inner slide closed. The vehicle has not yet been inspected by the Toyota dealership or insurance.

Transmission is making a wheezing noise

Air conditioning lines eroded and needed to be repaired after 26,000 miles/ 3 or 4 years. A/C line repair cost was $2500. Vehicle is garage kept and cleaned regularly during winter, it should not be having rusting problems, especially in this good of condition.

My 2021 Toyota Highlander experienced transmission problems mainly related to the transmission models. My vehicles reported issues such as whining or grinding noises, which were attributed to problems with the pinion shafts in the front carrier assembly.

My 2021 Toyota Highlander, purchased with 16k miles, has a leak in the AC system in the rear of the vehicle (as of May 2025, at 3 years 10 months into the vehicle's service, with 28k miles). This pipe runs the length of the car and costs $2000-$3000 to repair. This was confirmed at an independent service center that used leak detection dye to identify the problem. I am finding multiple reports of people having this problem in young Toyota vehicles (<4 years old) and with low miles. I believe this is a design flaw and not indicative of normal corrosion, as the vehicle does not exhibit corrosion elsewhere in the under carriage.

This is a supplemental complaint to add more detail to a prior submission. I am the original owner of a 2021 Toyota Highlander with 10,000 miles at the time of the issue worsening to the point that I finally broke down and was forced to pay the Toyota dealership's hefty diagnostic fee. The air conditioning system has failed due to a refrigerant leak in the rear A/C lines, specifically near the exhaust area under the vehicle. The dealership diagnosed the issue and quoted me over $3,000 to replace “all necessary components in the rear.” They offered no coverage or goodwill repair despite the vehicle’s age and mileage. Upon researching the issue for longer than a year at this point, I discovered far too many similar complaints from other Highlander owners (years 2019–2021) describing identical failures — typically rear A/C lines corroding, cracking, or leaking prematurely. In some cases, customers were told Toyota is aware of the issue but not issuing a TSB or recall. In other cases, dealers said no permanent fix exists. These repairs are prohibitively expensive and, in some reports, recurring due to poor line placement or dissimilar metal corrosion near heat sources. This significantly impacts safety in several ways: Impaired Visibility: The AC system is integral to effective defogging and defrosting of the windshield, especially in humid or cold conditions. Without it, visibility is severely compromised, increasing the risk of an accident. Driver Impairment: In extreme temperatures, lack of climate control can lead to driver fatigue, distraction, and reduced concentration, posing an indirect safety risk. I am reporting it to request NHTSA monitor the trend. This seems to reflect a possible engineering or design flaw, and the number of similar owner reports suggests it may warrant further review by Toyota and NHTSA. Customers should not be facing multi-thousand-dollar repairs on near-new vehicles with basic systems failing. Thank you for tracking this issue.

MY TRUNK WILL NOT OPEN OR CLOSE PROPERLY FAULTY SENSORS

Toyota continues to knowingly not remedy an airbag sensor issue. My vehicle has the light on indicating it is suffering from the same recall. I bought this car from them in 2024 and they sold it to me with the knowledge that there was a safety issue. I’ve tried to find a solution as this is a major safety issue. Toyota took my money in full for the car, yet can only offer me a loaner for 25 days. They said in CA, it most likely won’t get fixed until the end of 2026. I don’t have money. I have one car and I need a vehicle to transport to work and kids to school. This is not right and this is not safe. A remedy for people in CA that won’t be fixed for two more years that is an ACTUAL SAFETY issue , is not right. This is to document the safety complaint as the dealership continues to ignore the issue, and the 1-800 Toyota line continues to ignore it. All BBB complaints shows I’m not the only one. I can’t take a rental because they won’t pay me back, it’s not guaranteed, and I’m out another $40,000. They put people in impossible situations. The manager at the service center it’s your fault if you walk out of here without taking a loaner. You’re choosing to put your family at risk. And I said no, you’re offering me a loaner and you can’t guarantee a vehicle that will fit my family. I don’t know what to do.

The dictation had stopped working, can not longer send messages while driving.

The rear hatch has been causing me issues for quite a while. Last year, I would have to hit the close button once or twice for it to close. It would close a few inches, beep, and then stop. It has become much worse the last six months. I have to manually close the hatch myself because it won't go down all the way using the button. We took it to Cedar Rapids Toyota and they said this is a very common issue in this vehicle. They adjusted the hatch and lubricated it. Once they were done, they said it doesn't work any better. It costs over $1,000 to replace the parts and they can't get the parts until June because so many people are having the same issue. This vehicle needs to be recalled. Thanks,

Subject: Transmission Issue – 2021 Toyota Highlander Dear NHTSA, I am reporting a serious transmission issue with my 2021 Toyota Highlander (82,000 miles). I recently took it to the dealership for an unusual noise, and they diagnosed a transmission failure, quoting over $9,000 for replacement and service. After researching, I discovered Toyota has known about transmission issues in the 2021 Highlander since at least 2021. I have always serviced my vehicle at the same dealership, yet they never informed me of this known defect. Instead, they waited until my warranty expired to disclose the issue, despite my repeated maintenance visits where I reported the noise. I also found a 2021 Toyota document acknowledging transmission problems in this model, and many other owners have reported the same issue. It seems dealerships avoided addressing this until warranties expired, leaving owners with massive repair costs. This raises serious concerns about Toyota’s handling of known defects. I urge the NHTSA to investigate and take action to protect consumers from unfair repair costs and potential safety risks.

While pulling onto highway I heard a loud pop and scratching noise. Pulled off road and looked at vehicle from outside. When I looked on top I saw that the glass from sunroof had a hole and had shards like it had exploded from inside pressure.

Infotainment system, this system comes with talk to text abilities. However, the system will say it is not compatible with the device which isn’t true as this same device work from day one of owning this vechile. About a year after owning this vechile I began to start having issues with talk to text through Bluetooth. The only option now to respond to a text through the infotainment system is with a predefined group of messages. This is not the only case of this issue occurring as many models within the 2020-2021 Toyota have had the same issue.

The navigation has failed to perform properly since the car was new. I have complained about it/taking it in on more than one occasion. Now the car is three years old and has 23,000 miles on it. I am told I must pay to repair the navigation system which never worked properly in the first place. It directs me to roads that are closed;, finds the store I wish to go to, but then says I can’t navigate there;, sends me to a residential neighborhood when I have put in the address of a school;, changes the address I input while I am enroute. It is supposed to navigate to addresses in my contact list, but when I select a contact it then asks me to choose from a similar name in a different state than I have entered in my contacts. I am very curious to know if there have been other complaints or technical service bulletins.

On 2023, the bumper of my car fell while I was driving on the highway. At that time, I took my vehicle to the Toyota Dealership to get inspected and they inspected the vehicle and recommended me to take it to a Body Shop to get it repaired. I paid for the repairs from my pocket since they did not take any responsibility of the damages. On December 2023, I received a letter from Toyota telling me that my highlander has a recall due to bumpers felling off and needed to add some clips from the manufacturer. I opened a case and provided all the information requested by Toyota. At the end they asked me for a CCR document where none of the representatives I've spoke were able to explain what is this document. I provided receipts, Dealership inspection document, my car documents. Today 11.27.2024, I receive a letter telling me that they are not going to move forward with the reimbursement. The body shop that they recommended me does not provide a letter with the specific information they are asking me for. Toyota contacted them and confirmed they did the repairs and they still refused to pay for the manufacturer damages.

The Battery was leaking fluid, smoke was visible and rotten smell from the battery. Electrical secondary brake system came on the dashboard

Sunroof shattered while vehicle was parked. Nothing touched the vehicle. We were just sitting in the car when it happened.

[XXX], while driving on a [XXX], my 2021 Highlander Platinum unexpectedly shut down without ANY prior warning or indication of a malfunction. This abrupt failure put my safety, as well as that of my passengers and other motorists, at considerable risk. As a longtime Toyota customer, I have always valued the reputation of Toyota vehicles for their reliability and safety. However, this incident has significantly shaken my confidence in that reputation. I trusted that my vehicle, particularly one as recent as the 2021 Highlander, would perform safely and effectively in all driving conditions. The complete and sudden failure of the vehicle on a busy highway is not only unacceptable, but also alarming. I now find myself questioning whether I can continue to rely on this vehicle or the brand itself. After having the vehicle towed from obstructing a busy lane of traffic, the battery was jump started to get the car running again. I had NEVER had ANY issues with battery and all regular services had been completed at a Toyota Service Center, but several codes appeared on the dashboard after this incident advising the vehicle be taken to a dealer. Vehicle was taken to Toyota Service Center [XXX] for a diagnostic check, but they couldn’t find any error codes or issues with the vehicle. I contacted Toyota to thoroughly investigate this matter and address the underlying issue that caused the shutdown, so that I can regain confidence in its safety and dependability. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The sunroof exploded in 75 degree weather. My safety was put at risk by the sunroof exploding and others were put at risk that were following on highway from flying glass. The problem was confirmed by safelite. Toyota refuses to take any responsibility. The sunroof was inspected and repaired by safelite. There was no warning that the sunroof was going to explode. The vehicle maintenance is at the highest level.

This is my new car certified

The sun roof on this car spontaneously combusted. I was able to pull up many other complaints regarding the same issue on this car. This needs to be recalled. My [XXX] baby could have had shattered glass had we not had it closed. These sun roofs need to be recalled and inspected! INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

I had been driving for about 20 minutes at approximately 50-55 MPH when the check engine light came on. Seconds later, the red hybrid malfunction message displayed and I lost the ability to accelerate. I was able to pull over and I saw grayish smoke and flames coming from under the hood on the right side. I exited the vehicle and called 911. It took moments from the start to being completely engulfed in flames. Several loud pops or explosions happened during this period. The police and fire department arrived and extinguished it.

We were driving across the Texas panhandle at the posted speed limit of 75 mph. It was about noon, the outside temperature was about 60 fahrenheit & there was a cross wind of about 30 mph. There were no vehicles in front of me & the closest approaching vehicle was a good half mile away. No vehicles had recently driven past us from the approaching lane. There was a sudden explosion above us & through the 1-2" gap in the motorized retractable sunshade of our moonroof, I could see broken glass. Through that gap, some glass fragments fell in on us. I pulled over to stop, got out & inspected the roof, & the front glass panel was completely shattered & 75% gone. Many of the fragments were on the sunshade & I removed those. Going at about 40 mph we went to the closest small town where a mechanic removed some residual loose glass, vacuumed as much off the shade as he could, & patched the hole with cardboard held in place by duct tape so we could get home for a repair. If the shade had not been almost closed, we would have been showered with glass with risk of bodily & eye injury.

I have noticed that my vehicle tends to jolt forward as I’m applying the brakes to come to a complete stop.

Driving back from lunch with a friend we heard a pop and loud shattering sound as my sunroof glass exploded for no apparent reason. I called the dealer where I purchased the car 40 days ago with every extended warranty that I could. Toyota denied the claim stating that there was not any bulletins stating material defect and that the glass was not part of any warranty and I will have to file an insurance claim.

While slowing and braking to stops (approximately less than 20 mph), the vehicle will lurch/lunge forward. It feels like you took your foot off the brake pedal but you did not. This occurs randomly. It does not happen every time. There are no warning lamps, messages, etc., prior to or during this issue. The vehicle has ~39000 miles. This has been occurring for at least 20000 miles. Risk: If this occurs when close to pedestrians, other vehicles, intersections, etc., it could result in an impact. The dealer could not reproduce but did find online message forums that reported the same issue.

The Passenger rear tire burst automatically today around 8 AM morning. Unsure if this automatic burst is part of any recall or not but it was a scary burst with big noise with no warnings of low air pressure. A lot of time was wasted today and spent money to fix a new tire.

Driver side mirror glass started shaking all the time. The mirror frame is stable, but the mirror glass is shaking when car is idling and driving. Makes it almost impossible to use that mirror when driving

Driver side view mirror shakes a lot making it impossible to make things out in your mirror while driving. Very dangerous to see what is in your mirror.

my car experiences intermittent acceleration when applying the breaks. It lunges forward for some reason. It has also not stopped when hitting the breaks hard but lunges as well. I am using the last date that this happened.

Several minutes after leaving my vehicle once I parked and shut the engine routinely, it rolls back a hundred feet and crashes into another vehicle. When I come back I became aware of this as I noticed the back of the driver side of my vehicle is lodged into the side of another vehicle. This caused damage to both vehicles.

I have a 2021 Toyota Highlander XLE with a panoramic sunroof. on 5/11/2022 I was driving on the road when I heard an extremely loud explosion. I looked around and didn't see any damage, then I pulled off the road to discover that the sunroof had exploded. I called the dealership and they referred me to Safelite. Safelite took my information and called me back 2 days later to inform me that they don't stock the part I have to go to the dealer. I booked an appointment with the dealer (Sheehy), I took the vehicle in, they inspected, and I was told by Sheehy that "they've never heard of such a thing" and they were going to call the manufacturer to see if they will approve my repair under warranty. They called me back about a week later to say my claim for repair costs was denied due to, in their words "outside influences". There were no rocks, debris, etc. found that could have contributed to the moonroof shattering. Fortunately, I had the shades pulled otherwise I would have been covered in broken glass. There was no damage to the shade to indicate an object fell on it. After a quick google search, I saw that other SUV owners had experienced this same phenomenon and were told the same thing- outside influences caused this. Toyota should inform consumers about this issue and fix it no questions asked when this happens rather than try to brush it under the carpet especially when the vehicle is still under warranty. This presents a road safety issue as flying glass could get injure other people.

On May 24th I was driving back to work form my lunch break, had to make an additional stop before going back and in the moment I was to make a right suddenly the car would not stop or turn, no light were on at the moment, now the car is a total loss and I went trough the scariest time of my life after running into mangroves

This is in regards to a 2021 Toyota Platinum AWD with 8500 miles. While cruising at about 40 miles/hour, the car suddenly lost power, and an alpha numeric code popped on the digital display that said “Chip malfunction” and something else I don’t recall. It also said to see your dealer immediately. On the dash, the check engine light came on with a message that said “reduced engine power”. This message alternated with another alpha numeric code. I did not write down the actual codes because I thought the car would record them. I was able to roll onto a side street and turn off the car. After 5 min, I restarted the car and took it to the dealer later that day. They not only could not find a code in the record, the entire trip was not recorded, even though it’s on my Toyota app. First, they tried to say it couldn’t have happened because it was not recorded. Then, they said the recall regarding a power issue was the culprit, but also admitted the “fix” had nothing to do with, and would not affect, the engine. After insisting more be done to iD the problem and fix it, they agreed to keep the car and run a diagnostic. It turned up nothing except “maybe bad gas”. Really? We only use premium from reputable sources. I do not feel safe on the car and most certainly do not feel safe putting my child in it. I cannot believe they cannot find the problem.

I was driving with my daughter on the highway where all of a sudden I could here a loud noise on the top of my car. I opened the sunroof to see what's wrong only to see a Crack in the sunroof. Nothing hit the roof but it was cracked up. As I was driving it began to break up. If I had the shade opened I would have been hit with the glasses and I had my three year old in the car as well. Absolutely nothing hit the vehicle but it broke on its own.

My sunroof exploded. I reported it to Toyota USA and dropped my car off at the local Toyota dealership. We had to shut the sun shade to keep glass from falling in on us. The SUV is still in the shop and we have not heard back from them yet. I did not call the police or insurance yet. There was no warning. Nothing hit it. It just exploded.

Driver side mirror shakes when going greater than 25 mph. This does not happen on passender side, makes it more difficult to see object in mirror and more dangerous changing lanes on highways. First noticed after a few months of minimal driving.

While driving a piece popped off of the passenger door mirror. It flew off and hit the passenger door causing scuff marks before flying into traffic and causing the car behind me to swerve in traffic to avoid it from hitting their car or driving over it, which could have caused an accident. I wasn't able to recover the piece due to the incident occurring on the interstate. I did take the vehicle to the dealership (Serra Toyota - Birmingham, AL) in July and was told by the service technician that they had three other cars to come in with the same issue within the last month. Also, I was told that the entire mirror would have to be replaced since the manufacturer didn't make the piece alone. I was told that it would cost me $800 to replace the entire mirror. I should not be responsible for a faulty piece on the vehicle that was just purchased at the end of April. The technician told me that he would put in a ticket with the manufacturer, but I have not received a response.

The fixed moonroof appears to have exploded on its own while parked. No alarm was set off and no objects were found inside the vehicle suggesting an impact. There was no debris around the car. There were no storms or the vehicle is not parked near trees or ball fields. Dealer denies any known occurrence and states this must be from an impact and is not covered by warranty.

I was forced to change lanes quickly from the left lane to the left shoulder of an interstate when a double tandem tractor trailer moved into my lane of traffic. The interstate was dry and the left shoulder was in excellent condition and wide enough to accommodate my vehicle easily. All lane assist options were turned off, the driving mode was set to “economy” and the cruise control was turned to “off”. A few seconds after entering the left shoulder of the interstate, I felt the rear end of my vehicle sway from side to side for a few seconds. After the swaying ended, I thought there was a brief loss of vehicle control after which the vehicle returned completely to my control. My vehicle is a Toyota Highlander Limited AWD gas engine SUV with about 2700 miles when this occurred. I drove my vehicle without any emergency steering maneuvers 2700 miles prior to and 500 miles after this incident without any problems. I had my Toyota dealer examine the suspension, steering and event recorder of the vehicle and test drive it. They found the vehicle to be performing within manufacturers specifications and without any defect in the steering or suspension and found no codes found in the event recorder.

The answer to the above questions is UNKNOWN. I do not clearly remember the moments leading up to the incident. I was parked on the driveway of my daughters house. I was in my Toyota Highlander Hybrid 2021. We were stationary at the top of the driveway after returning because we had forgotten something. My grandsons were in the car but they were not hurt. The driveway is on an incline.  I am not sure what happened from here. As I exited the car it started to roll backwards. I tried to get back in to stop it but got knocked down by the open door and moving car. I fell. The car rolled over my legs, dragged me down the incline and I was stuck under the front bumper. The car stopped either because of the ABS when I was as the front of the bumper or because it was on level ground at that point. My son-in-law tried to put the car in reverse to move it off of me but said they could not get it to start. I was barely stuck and the neighbors just lifted the front bumper a bit and I rolled out.   I have some soft tissue damage (full thickness degloving to the bone on my left calf and 4 fractures (1 in each leg and a couple in my pelvis). I have been to the operating room 4 times, the emergency room three times and spent 19 days in the hospital. It is the first car I have had with a key fob, no physical emergency break and I have safely parked in on this driveway for 5 months. It does not make sense that it would be in neutral as I never use that gear but that seems to be what would have had to have happened for this to occur. l bought this car for all of the safety features yet this still happened so I am sharing it with you in case there are further safety features that can be developed to prevent such accidents in the future. If it had a real key and real emergency brake I do not think this would have happened.

The car was stopped at a red light and the car shook and slightly vibrated and shut off. No warning signs, no warning lights, just died. I was in the car with my twin 3 year olds, the AC shut off, everything shut off, the temperature outside was over 90 degrees and heavy traffic. I was very scared for my safety and very confused as to why a brand new car would die.

About 15 minutes prior to the incident, the interior shade cover was closed beneath the moonroof. Mostly sunny day about 85° F, about 55mph, the moonroof exploded. The sound was that of a shotgun, followed by wind noise and tinkling noises of shattered glass just beyond the shade cover. Upon external examination, 100% of the glass sliding moonroof was shattered, approximately 30% of the glass had departed the vehicle from a forward and central portion of the glass area. The remaining glass was bowed outward. The roof aft of the moonroof displayed 1-3 millimeter length flags of clear coat paint where the glass shards had etched the painted surface and the rear spoiler fairing panel over the aft hatch had gouges in the plastic composition along the upper surface of said fairing. All components on the vehicle were factory installed. Vehicle had 10,000 miles and was in service just over 5 months. There were no indications of an impeding problem. The moonroof was secured with tape and cardboard to prevent shards of glass from departing the vehicle. The dealership body shop estimates repairs at $4319. Safety threat: If shade were open at the time of explosive incident, shards of glass would fall onto driver and passengers, which might create a loss of control from panic (explosion was very loud and disconcerting) glass in facial area (between eyes and sunglasses) or falling into clothing at the neck area and creating a painful bloody situation at highway speeds. Shards of glass departing incident vehicle might reach a following vehicle (motorcyclist) depending upon upward trajectory of glass and forward speed. Might affect vehicles traveling in opposite direction. Driver following incident with window down might be exposed to shards of glass slip streaming into that vehicle.

I purchased my Toyota Highlander Hybrid only about 2 months ago. Since then, I've experienced several incidences of sudden acceleration. In a few of them, I was approaching a stop sign and began to slow down. Suddenly, I felt the car accelerate on its own. In both instances, I slammed on the brakes and the car jerked then stopped. There was one instance when I was going down hill and I was stepping on the brakes, but the car seemed to accelerate on its own until I stepped on the brakes again. Fortunately, there were no collisions. However, this is a serious safety problem.