Toyota Highlander water leak problems

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 Oct 13, 2025 · Airbags, Electrical · VA

Clog of evaporator box caused water intrusion into vehicle. Water leaked onto Airbag ECU causing malfunction and requiring replacement of Airbag ECU.

Filed Sep 10, 2025 · Electrical · NY

There is a voice listening device or microphone on the headliner right above the driver's side seat which leaks water. I see there is a recall for a windshield but it could be coming from the sunroof.

Filed Aug 28, 2025 · Airbags · OH

Water leaking into airbag area. Known leak issue per the federal safety agency [XXX] ) from defective roof rack attachment clips. Per Toyota, not covered by Toyota unless car still under warranty. Leak issue is common issue with many Toyota (RAV4, Highlander). I cannot tell if the potentially waterlogged airbag area is defective unless I get into an accident to test it. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Feb 27, 2025 · Body · 5 miles · OH

The contact owns a 2021 Toyota Highlander. The contact stated that rainwater leaked into the roof panel into the front driver’s and passenger’s side door panels, causing a mildew odor inside the cabin of the vehicle. The vehicle was taken to the local dealer who discovered mold was present inside the panels of the vehicle. The contact was informed that the interior headliner and headliner clips needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was offered. The failure mileage was 5.

Filed Jan 11, 2025 · Body · OR

Water leaks inside the car every time it rains. We checked the sunroof drain tubes. They are clear. It is getting in through the roof rail bolts. It runs down the pillars to the floor and underneath the floor carpet. The carpet is wet for long periods of time in rainy seasons. I am concerned there is going to be mold issues.

Filed Oct 9, 2024 · Body · WV

Water leaking into the A pillar where airbags are located due to faulty seals in roof rails.

Filed Jul 25, 2024 · ID

The clips on the roof rails are not sealed and it allows water to leak into the car through the roof. This was an issue with previous RAV4 vehicles and is continuing on with the Highlander design. The water enters the vehicle anytime it rains or the vehicle is washed.

Filed Oct 27, 2023 · OK

While driving in rain, I noticed drops of water coming into the car near the sunroof. I immediately drove to Jim Norton Toyota. The service technician told me that sunroofs are not waterproof. I went to Bob Howard Toyota for another inspection/more details. They informed me that it was a new design flaw. The sunroof sealant and gasket to do not align with the sunroof perfectly as older models do. Small drops of water will occur when it is raining. The "drip pain" underneath the back part of the sunroof will catch the water and the drain tubes will remove those from the car. They said drain tube cleanings are needed to not damage car from leaks. I had a 2009 Highlander Hybrid - same car, different year. It NEVER leaked or had water droplets anywhere. The seal and gasket met tightly against the car. I have never had any car that leaked. I would not have purchased a vehicle that purposely leaks water into a car.

Filed Jun 14, 2023 · Airbags, Body · TX

Water leak at sun roof caused by rubber seal failure in sun roof frame due to faulty material and or installation. Water damage to side air bag so tat it does not deploy properly & is a safety hazard. Mold carpet which is a health hazard & impedes drivers ability to drive.