2021 Toyota Sienna Hybrid Problems

SRS Airbag Malfunction, visit Dealer warning

SRS light has been showing up on the dashboard, off and on for 3 weeks. Diagnostic reader completed by the dealership states it is an airbag module malfunction of the 2nd row left passenger seat. The seat has never been removed, there have been zero accidents and no damage to the seat or wiring.

brake sleeps sometime when i press brake pedal i took car to dealer once,they said need time i did not have much time took another time, they reseted system still... my warranty is over now. rear seat,make shake noise and check rear seat sign on dealer can't find problem. did not do anything since new car. i do not know any other 2021 sienna drivers have same problem.

FAILURE: Brake control system. Vehicle intermittently surges forward while braking at low speed, most often through a curve — the brakes momentarily release and the vehicle lurches before braking resumes. Appears to occur during the transition between regenerative and friction braking. Vehicle available for inspection. SAFETY RISK: Unpredictable momentary loss of braking at low speed, in parking lots, residential streets and curves where pedestrians and other vehicles are close. Driver cannot anticipate it. WARNING LAMPS: None. No lamp, no message, no stored trouble code. Present since early in ownership; purchased new September 2021. CONFIRMED BY DEALER: No. Reported to a Toyota dealer in 2022 under warranty. Dealer test drove, could not reproduce the intermittent condition, took no action. Also reported in writing to Toyota in August 2022; no substantive response. MANUFACTURER REMEDY: In May 2024 Toyota issued TSB T-SB-0047-24, a brake control module software update for this exact low-speed braking condition on 2021-2022 Sienna Hybrids. Warranty had lapsed, so it was applied at owner expense in late June 2026 at ~156,000 miles. The defect persists after Toyota's own remedy. The surge still occurs, including within the past week at ~157,000 miles. REQUEST: A TSB is not a recall — owners are not notified, and the software remedy did not eliminate the defect on this vehicle. Request that ODI evaluate whether this condition warrants a defect investigation and recall.

brake sleeps sometime when i press brake pedal i took car to dealer once,they said need time i did not have much time took another time, they reseted system still... my warranty is over now. rear seat,make shake noise and check rear seat sign on dealer can't find problem. did not do anything since new car. i do not know any other 2021 sienna drivers have same problem.

The electronic driver's seat motor and track assembly failed completely on my 2021 Toyota Sienna (VIN: [XXX]) at less than 18,000 miles. The seat is permanently seized in a fixed position. This creates an immediate safety and crash-protection hazard, as drivers of different heights cannot safely adjust their distance from the steering wheel airbag or properly reach the pedals. Toyota corporate is refusing to repair this premature manufacturing defect on a known problematic seating system, leaving a severe safety risk unresolved. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The contact owns a 2021 Toyota Sienna Hybrid. The contact stated that the passenger's side rearview mirror detached and the rear liftgate door inadvertently opened while parked in the garage. The vehicle was taken to the dealer but was not yet diagnosed nor repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 9,000. The VIN was unavailable.

THE 2021 SIENNA XLE PLUS AND ENTERTAINMENT PACKAGE DID NOT INCLUDE A DIGITAL REAR VIEW MIRROR IN THIS TRIM LEVEL. THE NEW SIENNA IS A BRAND NEW MODEL WITH A MASSIVE DESIGN FLAW, A HUGE TV WITH ZERO VISIBILITY OUT THE REAR OF CAR. IT'S UNSAFE. MANY PEOPLE WILL NOT TEST DRIVE WITH THE TV DOWN TO SEE THE SAFETY ISSUE. WE DIDN'T REALIZE IT TILL KIDS PUT THE TV DOWN DAY LATER. SEEMS TO HAVE SADLY MADE IT THROUGH QUALITY CONTROL PROCESS AT TOYOTA. YOU CAN NOT SEE CARS RIGHT UP ON YOU AT STOP SIGNS, CARS APPROACHING ETC IT NEEDS A SAFETY RECALL AND A MODIFICATION.WE HAVE HAD CAR FOR 3 WEEKS.

The rear power liftgate hinges on my 2021 Toyota Sienna failed structurally under normal, everyday operation. The power liftgate motor and struts appear to exert uneven or excessive pressure on the rear hatch assembly, causing the metal hinges to crack. Before the failure, we noticed a loud popping/grinding sound when opening the hatch, which quickly progressed to the liftgate binding and misaligning. This is a severe safety hazard because the structural failure prevents the heavy rear hatch from closing or latching securely, creating a risk that it could fly open while driving, dropping cargo onto the roadway or exposing passengers. It also creates a risk of the heavy door falling unexpectedly on someone loading the vehicle. The vehicle had to be taken to a dealership body shop for structural repairs due to the cracked metal, costing me over $1,500 out of pocket. Toyota has not issued a recall or good faith reimbursment for this known design defect.

My liftgate has been making loud noises upon closing. The dealership checked it and diagnosed that the trunk door is mis-aligned, leaving a gap so that the door WOULD NOT SECURELY CLOSE. I was referred to the body shop to have the shocks and hinges changed. Further discussions mentioned this was a common problem with the Toyota RAV-4 where the hydraulics fail causing a bad alignment therefore affecting the hinges. Although my vehicle is a Toyota SIENNA, I had asked if this was caused by mishandling on my part (ie, slamming/ forcing the door or stuffing the cargo) but the technician mentioned that there was nothing I could have done to prevent it nor done to have caused the hydraulics to fail or go bad. There were no lamps or alerts that warned me of the problem other than the "scraping noise" upon closing that was getting louder ever since. The problem had been assessed and confirmed by the body shop.

The front passenger door lock actuator does not work properly causing the door to stay locked or unlocked despite attempts to change the door lock through the internal power locking system or remote key. This presents a safety issue in that it requires a manual lock/unlocking of the door should an emergency situation arise and expeditious ingress or egress from the vehicle be required. The door actuator is presently working intermittently and appears likely to fail permanently in the near future.

FAILURE: Blind spot monitor module failed due to a corroded internal electrical connector. The failure disabled both the Blind Spot Monitor (BSM) and Rear Cross-Traffic Alert (RCTA). Both remain inoperative. The failed component has not been replaced and is available for inspection. SAFETY RISK: Two active safety systems are disabled. The vehicle no longer warns of vehicles in the blind spot during lane changes, and no longer warns of cross traffic when backing out of parking spaces or driveways. WARNING LAMPS: Yes. Multiple warning lamps illuminated simultaneously in February 2026, including BSM and RCTA malfunction messages. No prior symptoms or gradual degradation. CONFIRMED BY DEALER: Yes. A Toyota dealer diagnosed the corroded connector as the cause. Repair quoted at approximately $2,500-$3,000. Repair not performed. INSPECTED BY MANUFACTURER: Diagnosed by a Toyota dealer. Goodwill assistance was requested from Toyota and declined, on the stated grounds that the vehicle had not been regularly serviced at a Toyota dealer. NOT A WEAR ITEM: A sealed electrical connector that corrodes to failure is a component defect. No step in the manufacturer's published maintenance schedule inspects, services, or protects this connector — no owner action could have prevented it, and service history has no bearing on a connector that no service procedure touches. Vehicle purchased new September 2021; failure occurred at approximately [XXX] of age. REQUEST: Request that ODI evaluate whether the BSM sensor and connector design used on this vehicle is inadequately sealed against moisture intrusion, resulting in premature failure of two active safety systems. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

We were stopped at a stoplight. As soon as we stepped on the gas pedal, there was a loud clunk sound and plastic parts started flying out from under the car. We immediately pulled over. Oil was spilling out everywhere. The transmission oil pump was laying on the inside of the engine compartment. We had towed to Toyota. They diagnosed a bent piston went through engine which also caused a hole in the transmission. I had it towed for a 2nd opinion. Neither toyota or the 2nd opinion had ever seen anything like it. My mechanic also said there are a bunch of other suspension parts that were damaged due to the violent stop of the engine. There are a few of the same incidents online in chat rooms. The car is totalled and we are out of a car now.

The contact owned a 2021 Toyota Sienna Hybrid. The vehicle was parked in the driveway when an explosion occurred; the vehicle burned down. The contact was inside the residence when a loud noise was heard, and the house "rocked." The contact ran to the front of the house to investigate and noticed that the vehicle was engulfed in flames. The fire damaged the driveway, melted the garage door, and melted a landscaping retaining wall. The fire damaged the post on the front porch. The contact and her family were unable to exit through the front door due to the fire and used the sliding kitchen door to exit the residence. The fire department was called to the scene. Per the contact, three fire trucks were at the scene. The fire department informed the contact that the fire went up to 3,000 degrees. The fire department concluded that the fire started from underneath the driver's back panel. The contact stated that the gas tank was underneath that area and believed the gas tank may have contributed to the fire. The towing company towed the vehicle to a towing yard, and it was later picked up and towed to an unknown location. The insurance company was notified and declared the vehicle a total loss. The manufacturer was made aware of the failure and advised the contact that an inspection was needed on the vehicle and asked for the location of the vehicle.  However, the contact was awaiting the results. The failure mileage was approximately 80,000.

Unexpected failure of the acceleration pedal to accelerate from a complete stop to a go at an intersection. The electric vehicle (EV) motor began accelerating up to about 3 mph than instantly had a failure to accelerate, even with the gas pedal continuously pushed to the floor. After about 4 to 5 seconds the engine kicked on and began accelerating. The failure seemed to occur during the EV motor swapping over to the gas powered engine. This has been the fourth occurrence and can be extremely dangerous at intersections with oncoming traffic. No fault codes or check engine lights came on.

The car jerks when coming to a stop. Like when the regenerative system is disengaged it jerks. For the Adaptive cruise control the car will accelerate instead of braking when another car merges in front of you.

Both front struts of the vehicle have failed and are leaking. There is only 36,000 miles on this vehicle when they should last 200,000 miles per Toyota's service department. Toyota refuses to acknowledge this is their problem and that it's a "wear and tear' part. However clearly these parts should not fail after so little usage.

We were stopped at a stoplight. As soon as we stepped on the gas pedal, there was a loud clunk sound and plastic parts started flying out from under the car. We immediately pulled over. Oil was spilling out everywhere. The transmission oil pump was laying on the inside of the engine compartment. We had towed to Toyota. They diagnosed a bent piston went through engine which also caused a hole in the transmission. I had it towed for a 2nd opinion. Neither toyota or the 2nd opinion had ever seen anything like it. My mechanic also said there are a bunch of other suspension parts that were damaged due to the violent stop of the engine. There are a few of the same incidents online in chat rooms. The car is totalled and we are out of a car now.

FAILURE: Blind spot monitor module failed due to a corroded internal electrical connector. The failure disabled both the Blind Spot Monitor (BSM) and Rear Cross-Traffic Alert (RCTA). Both remain inoperative. The failed component has not been replaced and is available for inspection. SAFETY RISK: Two active safety systems are disabled. The vehicle no longer warns of vehicles in the blind spot during lane changes, and no longer warns of cross traffic when backing out of parking spaces or driveways. WARNING LAMPS: Yes. Multiple warning lamps illuminated simultaneously in February 2026, including BSM and RCTA malfunction messages. No prior symptoms or gradual degradation. CONFIRMED BY DEALER: Yes. A Toyota dealer diagnosed the corroded connector as the cause. Repair quoted at approximately $2,500-$3,000. Repair not performed. INSPECTED BY MANUFACTURER: Diagnosed by a Toyota dealer. Goodwill assistance was requested from Toyota and declined, on the stated grounds that the vehicle had not been regularly serviced at a Toyota dealer. NOT A WEAR ITEM: A sealed electrical connector that corrodes to failure is a component defect. No step in the manufacturer's published maintenance schedule inspects, services, or protects this connector — no owner action could have prevented it, and service history has no bearing on a connector that no service procedure touches. Vehicle purchased new September 2021; failure occurred at approximately [XXX] of age. REQUEST: Request that ODI evaluate whether the BSM sensor and connector design used on this vehicle is inadequately sealed against moisture intrusion, resulting in premature failure of two active safety systems. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

The car jerks when coming to a stop. Like when the regenerative system is disengaged it jerks. For the Adaptive cruise control the car will accelerate instead of braking when another car merges in front of you.

HEADLINER CUT TOO LARGE, DOESN'T HOLD REAR PASSENGER CLIMATE CONTROLS, CLIMATE CONTROLS FALL OUT AND HIT REAR PASSENGERS. THIS HAPPENS AT ANY SPEED.

THIRD BRAKE LIGHT CONDITION POOR VISABILITY TO OPERATOR ( REAR WINDOW) WHEN BRAKE IS ACTIVATED IN LOW OR DARK LIGHTING CONDITION(S) THERE IS REFLECTION OFF GLASS AND REAR DEFROST ELEMENT(S) WHICH CAUSE LIMITED REAR VISABILITY OUT OF REAR WINDOW GLASS.

The contact owns a 2021 Toyota Sienna equipped with Cooper Tires, Tire Line: Discoverer True North, Tire Size: 235/35/R17, DOT Number: RN811KW1322. The contact stated while his wife was driving approximately 65 MPH, the front driver's side tire sustained a blowout. Upon inspection, it was discovered that the sidewall of the tire had failed. The cause of the failure was not yet determined. The contact stated that prior to the failure, the tire was taken to the local dealer regarding slight bulging on the sidewalls, but the contact was informed that the tires were safe for driving. The manufacturer was not contacted. The failure mileage was 37,000.

Unexpected failure of the acceleration pedal to accelerate from a complete stop to a go at an intersection. The electric vehicle (EV) motor began accelerating up to about 3 mph than instantly had a failure to accelerate, even with the gas pedal continuously pushed to the floor. After about 4 to 5 seconds the engine kicked on and began accelerating. The failure seemed to occur during the EV motor swapping over to the gas powered engine. This has been the fourth occurrence and can be extremely dangerous at intersections with oncoming traffic. No fault codes or check engine lights came on.