2021 Toyota Highlander Electrical System Problems

Trunk has stopped working. It loudly beeps and will not open on its own. Trunk has to be manually opened and shut with great force to be used.

Vehicle: 2021 Toyota Highlander XSE Approximate Mileage: 92,000 Location: Boerne, TX (Texas Hill Country) ⸻ Summary of the Problem: My vehicle experienced serious electrical failure after heavy rainfall in the Texas Hill Country, where catastrophic flooding recently occurred. At a red light, the dashboard began flashing, power windows stopped working, and the electronic parking brake would not disengage. I was nearly rear-ended with my children in the car because the vehicle temporarily lost responsiveness. ⸻ Pattern of Issue: This problem only occurs after rain. Once the vehicle dries out, the systems return to normal. Toyota tested the battery and alternator and found no faults. The dealership and Toyota Corporate have been notified, but they have so far refused to approve a Goodwill Repair or perform deeper inspection for water intrusion into the fuse box, firewall harness, or Body Control Module (BCM). ⸻ Suspected Cause: I believe there is water intrusion due to a design flaw, likely through the windshield cowl or firewall. Other Highlander XSE owners have reported nearly identical symptoms following rain exposure. Toyota has issued service bulletins in the past about water reaching electrical components in other models. ⸻ Safety Concern: This is a serious safety issue. A near-crash involving my children occurred. If Toyota does not resolve this issue and it leads to an accident, I will hold them fully accountable. I am reporting this so it can be formally investigated and linked with similar complaints.

My SUV is having issues with the tires air and also the sensors are not working properly

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

Since I got his vehicle i satated to the Toyota that having the breaks problem and dash is not working properly and blind spot is not working on time

The navigation display unit failed in my 21 Toyota Highlander. It randomly flashes causing a driving distraction as it attempts to reboot, but then fails to turn on.

[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 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...

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

The start/stop operating system failed. When the engine cut off while waiting for train to pass, the engine went to turn over and completely stopped the vehile. Although the car would not start, I was unable to cut the car off completely. It would say ignition on. The lights in vehicle were on. Running the ac caused the car to say high power consumption but there was no way to cut vehicle off without removing the battery to reset the vehicle. Caused the car to malfunction while sitting at a complete stop. Also cause the parking break to engage and I was unable to disengage parking break. A message came across saying parking break unavailable. My safety and others were put at risk because had it happened at any other time a crash would have been caused. It caused a roadway to be blocked off which caused confusion and near accidents.

The Check Engine light came on and I took it into Toyota of Downtown dealership where I was receiving periodic maintenance. After 2 days, they said the light was out but they hadn't found the cause. I could either leave if for a few more days or take it and bring it back if the light came on again. This was early August. I chose to take the car & when the Check Engine warning light came on again, I took it in on Aug 15, 2024 before I left to Portland to give them more time. I returned on Monday & couldn't reach them. The next day they informed me that while on a test drive, there was a loud bang, it started smoking and by the time 911 arrived it was on fire. After a 2 month investigation by Toyota's Engineering Analysis fire inspection, they concluded Toyota was not involved. The dealership has not provided me with the report although I've requested it but they aren't accepting responsibility either although it was in their possession when the fire occurred.

The vehicle has accelerated suddenly when I apply the brakes. It has happened on multiple occasions in different circumstances. I was heading up a hill into a slow stop at a stop sign and once I applied the brakes it suddenly jolted forward for a second until I slammed on the brakes more over riding it. I have had the car for a week and thought it could be just happen stance but it has happened multiple times. The first time there was a car in front of me as I applied the breaks and it is terrifying as I almost crashed into them.

The doors lock and sometimes don't lock with the key

I came to a stop sign in my neighborhood on Windy Drive and I heard what sounded like a gunshot. I immediately put my vehicle into park and got out and noticed that the sunroof glass was shattered. The best description I can give is the glass looked like a volcano where the broken pieces were facing upward. I then proceeded to my local Toyota dealership located in Alexandria, Louisiana. They told me my car was out of warranty and provided me with a quote of $1,450.00. I believe that this occurred due to a defect from the manufacturing process and I don't think the consumer should be responsible for the cost to fix the sunroof. After researching on the internet, I see several complaints from other Toyota owners that have experienced the same incident and I feel this should be a recall on Toyota's part. I am frustrated that I have to pay $1,450.00 for damage that I know was a manufacturing defect after I researched and found hundreds of other consumers with the same experience.

Upon starting my 2021 Highlander Platinum with 10,700 miles on it several warning lights repeatedly came across my display including reduced engine power, brake system malfunction, pre collision system malfunction. See your dealer. No codes showed up on their scan but every time they cleared the screen the messages came back. They decided it was a bad knock sensor. Then I received a call that a critter had chewed wires and they might find further damage. I was surprised because I’ve been in my house for 45 years and I’ve never had a critter in my garage. The service manager said “Toyotas attract critters because of the covering they use on the wires.” I said, “Soy?” And he said, “Yes”. So, isn’t this a manufacturing defect? How many times a year is this going to happen? I’ve owned Toyotas for 27 years. I’ve never had a problem until this car. I’m also having problems with the navigation system, 2 visits to the dealership and 45 minutes on the phone with the Toyota Engagement Center.

Vehicle was driving at highway speed, transitioning to off ramp. Warning lights came on stating Braking Power low. Brakes proceeded to fail. Stepping on brakes did nothing but initiate a stuttering response. Vehicle would not slow down. Rolled into dealership that was luckily .5 miles away. It was diagnosed to be a wheel speed sensor. A sensor failing should not cause a vehicle to be unable to brake. Shocked and traumatized over the incident.

Recently purchased this Highlander on August 2021. On 11/29/21 at around 8:00 AM, the Check Engine light illuminated resting stop at a red light. Engine still running. Took the vehicle to the dealership at 9:45AM. Vehicle was found to have had misfires as a result of bad gasoline. I have been pumping at the same gas station ever since I bought the vehicle. If it was the bad gas, this issue should have happened sooner. Now, the dealership is telling me to pay for the diagnostic fee which they claimed it was my fault. The vehicle is under warranty. Another non-power/fuel issue that came with the vehicle was a loud wind noise when reaching 40 MPH. The noise is very annoying, like someone whistling into your ear. The dealership is ordering a part to fix this issue. The vehicle is still at the dealership.

I purchased this 2021 Highlander on April 3rd 2021. Power steering Malfunction, SRS Airbag system Malfuction first happened on April 21th 2021 when I started the vehicle. the car was towed to the dealer ship. the dealer simply re-set the system and asked me to unplug the tracker device which was installed by insurance company. Because they suspected the problem was caused by the interference from the device. I unpluged it. However, Power steering Malfunction, SRS Airbag system Malfuction happened again on May 21th 2021 when I started the car. I went to the dealer who then let Toyota involved this time and changed the battery. However, Power steering Malfunction, SRS Airbag system Malfuction happened for the third time on May 28th 2021.

Both of the front door lock actuators went out, so the vehicle won’t lock at all & I can’t use my Toyota app that I pay for. The left back door/hatch rail that lifts up the door is making a loud sound upon opening & getting stuck when opening. Have to push the open button several times or open it manually to get it to open at all. Have taken it to the Toyota dealer to inspect both & both are costly to repair. Can’t find either of the parts anywhere, so I’m guessing a lot of others are having these issues as well.