2021 Toyota Highlander electrical problems

Filed Oct 11, 2026 · Electrical, Visibility · UT

On November 19, 2025, the 12.3-inch infotainment display in my 2021 Toyota Highlander Limited went black and never recovered. That screen is the only display for the rear-view backup camera. With it dead, there is no backup camera image when reversing. The failure started as an intermittent blank screen with the reverse camera still working, then progressed to a fully dead screen including the backup camera display. A replacement display unit did not fix it. Toyota has acknowledged this defect in Technical Service Bulletin T-SB-0055-22, which identifies the integration control sub-assembly (part 840C2-48010) as the cause, but has not issued a recall. Toyota service repeatedly diagnosed the problem as a failed head unit. I replaced the head unit at my own expense and the screen still did not work. When I returned to the dealer, they refused to perform further diagnostics, stating the diagnostic cost would be as much as the head unit replacement.

Filed Sep 17, 2026 · Brakes, Electrical · 123,000 miles · CA

The contact owns a 2021 Toyota Highlander. While driving 20 MPH uphill, the messages "Engine Failure," "Brake Failure," and "Pull Over to A Safe Place, See Owner's Manual" were displayed, and several unknown warning lights illuminated. The contact turned off and restarted the vehicle, but the failure persisted. After a second restart, the message "See Dealer" was displayed with the check engine warning light illuminated. After a third restart, the vehicle was driving rough while the accelerator pedal was depressed. The vehicle was taken to the dealer. The manufacturer was notified of the failure by phone. The failure mileage was approximately 123,000.

Filed Sep 3, 2026 · Electrical · FL · fire

On August 24, 2026, my vehicle was parked, turned off, and locked for more than 6 hours in a parking lot. Without warning, the vehicle experienced a spontaneous thermal event/self combustion. The fire and thermal damage were entirely localized to the dashboard area inside the passenger cabin. The engine compartment, battery area and front mechanical components remained completely unaffected by the fire. The vehicle was off, motor was cold and car was closed and parked for about 6 hours when this incident occurred.

Filed Jul 1, 2026 · Body, Electrical · MO

The back hatch of the car has issues closing regularly. Nearly half of the time you push the button to shut the back hatch when it is open it will not close and has to be shut manually. Typically, it shuts an inch or two and then beeps at you and when you push the button again nothing happens but beeping. This is an issue because it is very difficult to close. Even as a 6' 200+ lb man who does strength training regularly, shutting the back hatch is difficult to do manually let alone for my much smaller wife. This has let to her having to ask for help from strangers in a parking lot to help close the door which is unsafe, particularly since we have small children. Toyota has acknowledged that this is a known issue and have stated that there is nothing that they can do to fix it. This acknowledgement came when the car was very new and my father was the owner and again just a few months ago when we brought up the issue again with Toyota.

Filed Jun 11, 2026 · Airbags, Driver assistance · NC

Four days after I took delivery of this used vehicle (April 25, 2026), multiple warning lights appeared at once: BRAKE, ABS, PARK, Check Engine, Blind Spot Monitor Unavailable, and RCTA OFF. An independent Toyota dealership diagnosed the vehicle April 27-28, 2026 (approx. 109,000 miles) and found (1) water leaking into the rear hybrid battery area through a sunroof drain "installed incorrectly," causing a Brake System Control Module low-voltage code, starting issues, a headlight only partially functioning on one side, possible air in the brake system, and a musty HVAC odor; and (2) blind spot monitor fault code C1AC2 (Slave Module Horizontal Axis Misalignment) - the blind spot and rear cross-traffic monitoring systems do not function reliably. At a second visit on May 4, 2026, recalibration was unsuccessful; per Toyota procedure the only remaining option is replacing the right-rear blind spot sensor. The technician wrote the cause is a mystery, "whether it be body damage related or electrical short." Toyota service records show the same C1AC2 code was documented during the selling dealer's own pre-sale inspection, and that in December 2024 another Toyota dealership pulled the rear bumper and found the RR blind spot sensor bracket bent, causing incorrect readings - a recurring safety defect that prior calibrations and repairs have not resolved. Separately, federal safety recall 23V865 (occupant classification sensors; the passenger airbag may not deploy as designed) was open and incomplete when I purchased the vehicle and remains incomplete, and Toyota service campaign 25TD01 (rear traction motor cable corrosion) is also outstanding. The defect has been reproduced and confirmed by two Toyota dealerships, reported to the selling dealer in writing, and reported to Toyota's customer-care center. The vehicle is available for inspection upon request. No crash, fire, or injury.

Filed Apr 10, 2026 · Electrical, Engine · GA

The vehicle experienced a transmission failure at approximately 62,000 miles, which required a transmission replacement. Toyota replaced the transmission with a rebuilt transmission. Immediately after the repair, the vehicle began experiencing multiple issues that were not present prior to the repair. The vehicle initially would not reverse, and the battery was drained shortly after the repair was completed. Following the repair, the vehicle has continued to experience ongoing electrical malfunctions, including dashboard warning lights, system alerts, and dash lights flashing during remote start. The vehicle has also developed a rattling noise underneath the vehicle. The exact failed component has not been clearly identified. The dealership has provided changing diagnoses and has not provided written diagnostic documentation despite requests. The vehicle has been inspected by the dealership multiple times; however, the issues have not been resolved. During a recent diagnostic, the dealership stated that the catalytic converter is now the issue, but this does not address the ongoing electrical problems. These issues raise safety concerns due to unpredictable vehicle behavior and potential failure of critical systems while driving. Warning lights and system errors began appearing after the transmission repair and have continued since that time. The vehicle is available for inspection upon request.

Filed Mar 31, 2026 · Driver assistance, Electrical · FL

The vehicle experiences intermittent power steering malfunction while driving. Warning messages including “Power Steering Malfunction” and “Low Voltage Abnormality” appear, and the steering wheel becomes stiff and difficult to turn. This has occurred multiple times during normal driving conditions, including at low speeds and while turning. When the issue occurs, it requires increased effort to steer, creating a risk of loss of control. Additional warning messages have included AWD malfunction, pre-collision system malfunction, and lane tracing assist malfunction. These alerts appear simultaneously with the steering issue. The problem began shortly after purchase and has continued intermittently. The vehicle has been inspected, but the issue has not been resolved. This condition creates a safety risk, especially when driving with passengers.

Filed Mar 2, 2026 · Body, Electrical · OK

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.

Filed Feb 2, 2026 · Body, Electrical · AL

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.

Filed Nov 28, 2025 · Electrical · CA

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