When driving normally in dry conditions, the vehicle stability control engages when making slow turns at about 45 to 55 mph. It happens mostly when steering to the right but can happen when turning left. This results in dangerous driving conditions where the brakes unexpectedly engage or the car down shifts to a lower gear. It has almost caused a wreck and has placed me and others in danger. The problem began about 2 to 3 years ago and has become progressively worse. Other owners of this make and model have reported similar issues without resolution by Toyota, dealers or auto repair shops. I am only able to resolve the issue by removing the fuse that controls the stability control system. See https://www.cargurus.com/cars/discussion-C9152_ds656326 for one example of a discussion thread. Given the pervasiveness of this problem, it is apparent that this is a systemic problem with the engineering or manufacturing of this vehicles and Toyota should be held accountable for this potentially life threatening problem.

- Cary, NC, USA

My vsc and slip dashboard indicators go on while I drive on dry road at speeds between 40-50 mph. The car then gives me kick back on steering and braking, almost as it losing control of my vehicle. It then goes away randomly. It is difficult to replicate the situation but it tends to occur on speeds above 35mph and on a curved road steering.this has occured while on the highway and on regular roads.

- East Stroudsburg, PA, USA

While driving, the traction control system warning came on when the roads were clear and dry. Also, the automatic braking started going off when making turns on clear roads. Whenever we traveled the highway and were making a turn at greater than 35 miles per hour, the warning sounded and the brakes went off.

- Boise, ID, USA

On inclines, the vsc light would come on, clicking noise near the steering column. The car would lose power. I have mechanics checked out. Cv joint and ball bearing replaced. Problem persists.

- Kingston Springs, TN, USA

About a five years ago the slip indicator light (car with swervy lines) started coming on intermittently while turning on highways etc. (but not when any risk of tires slipping). I brought it to Toyota three different times over the years and Toyota always states they can not duplicate issue and states they can?T fix it but maybe drive slower (really it has nothing to with my speed after years of dealing with this its been something we just deal with). The vsc light also comes on and alarm sometimes sounds while driving. Two more trips to Toyota and several visits to different mechanics and nobody can find out the problem. In the last 6 months the ABS system is also being activated without me applying the brakes. It does it without warning. All of these issues can be on a curve at different speeds or on a slight or medium turns (not real sharp turns), going uphill or downhill and left or right. Our van has about 150,000 miles on it now on 2020 but when the problem first started it only had around 110,000 miles on it. We have changed brakes, tires, rotors, brushing on advice from different mechanics to try to fix the issue. Nothing works. Toyota cannot figure it out. It's becoming more dangerous because now the ABS is being activated with this problem. I can't tell if my brake lights come on so that drivers behind me can tell that I"M slowing down very quickly. This jerks those in the car and I?M afraid we may lose control. I have read on different web sites that this is common with a Toyota and it's just not my van. If I had the money I would buy a different vehicle but being on a fixed income I don't have the luxury to do so. How can a car company have so many complaints from consumers about this common problem but still can't tell us how to fix it" it's Toyota design they should be able to tell the consumer what is causing this issue and how to fix it.

- Gresham, OR, USA

Vehicle would engage brakes by itself and vsc and traction control lights would start flashing and beeping when going around curves or hitting bumps in the road. This was frightening, and caused me to not in good conscience sell the vehicle outright to another person, so I lost thousands of dollars by trading it in. This happened intermittently for over a year. Estimated financial loss $4000.

- Cincinnati, OH, USA

I was driving on the freeway at approximately 70mph on dry asphalt on a sunny day when the stability control warning light came on along with rapid beeping. What was the most concerning was that the breaks activated twice causing me to have a near panic attack and I didn't think I had control of the vehicle. After a few seconds, the beeping stopped and I had full control of the vehicle again. There was no apparent cause for these safety features to have been engaged and no longer feel safe driving this vehicle. This is not the only time it has happened but it was the scariest. The other times have been at slower speeds and the brakes don't always engage. I have read numerous posts online describing the same issue with other Siennas and it doesn't seem like Toyota wants to do anything about this extremely hazardous issue.

- Sacramento, CA, USA

When we go on curvy roads, a clicking starts. It sounds as if it is coming from under the dash near the steering. Once that starts up the traction control malfunctions. The warning alarm comes on and the brakes engage on their own. It doesn't seem to matter how fast or slow we take the curve. This started about a year ago and continues to get worse. I've taken it to the mechanic but he can't replicate the problem because the road are mostly straight there and they couldn't physically see anything wrong. For what its worth, the problem happens when the roads are dry or wet. The tires are good and so is the pressure. This seems to be a common problem in this model of car and especially this particular year. For examples: Https://www.siennachat.com/threads/traction-control-malfunctioning.44474/

- Malibu, CA, USA

While driving with my autistic children the check engine light, the vsc light and the trac off light all came on and the wheels locked up on the right side and through the van into a ditch. This is very dangerous since this vehicle was made for families. I am now keeping a log and I do plan on retaining an attorney as no one has addressed this issue as a safety hazard.

- Alvarado, TX, USA

Car engenders self braking and cutting power off

- Stamford, CT, USA

The traction control, stability, and ABS engage in turns (steering input) ranging from speeds of 25-55 mph. It happens on flat surfaces, inclines and declines. The turn range from sharp turns to slight turns that there is no reduction of speed to navigate the turn. When it occurs the vehicle rapidly decelerates and pulls to the right. When trying to accelerate in a turn the vehicle will not accelerate until there is no steering input. Dealers and mechanics can not determine the cause. It has been occurring daily for about 6 months. This has caused many near crashes.

- Boones Mill, VA, USA

While driving on a slope, incline or decline, my traction control light ( car with squiggles behind it) comes on, a loud 'beep beep beep' sounds, and my car brakes on its own. Always happens while in motion. Highway driving. 90 percent of the time while on an incline or decline. It scares the heck out of you causing an unsafe condition. Additionally, when the brakes apply, it pulls you out of your lane. The first occurrence was 3 weeks ago. Has happened multiple times since. It doesn't seem to be intermittent anymore. You can count on it happening when your on a slope.

- Bloomfield, NM, USA

The traction control erroneously engages under normal driving conditions, which in turn activates the ABS. This causes sudden and unexpected braking. This is dangerous and could lead to loss of control of the vehicle.

- Temecula, CA, USA

While driving the vsc/ABS system comes on unexpectedly causing vehicle to brake and effect steering. It is most frequently noticed when steering on curves 30-40 mph. I have replaced tires, front steering components and dealer cannot duplicate. I believe wheel speed/yaw sensor calibration is affecting the vsc system. This is a very scary situation to be in that could lead to a serious accident. Your braking and steering affected all at once unexpectedly is dangerous. Please investigate and provide solution asap.

- Mooresville, NC, USA

The contact owns a 2008 Toyota Sienna. When the contact switched lanes or made a turn, the brakes activated on their own. The failure occurred on flat or curved roads and while driving 30 mph. Sometimes the brakes worked properly, but sometimes they did not work at all. The contact also stated that the vehicle would occasionally accelerate and decelerate on its own and the steering wheel made an abnormal ticking noise. Furthermore, the vsc and traction control indicators illuminated. The vehicle was taken to Toyota knoxville (10415 parkside dr, knoxville, tn 37922), but they did not assist. The vehicle was then taken to fox Toyota (228 fox family ln, clinton, tn 37716) where it was diagnosed that a steering angle sensor needed to be installed. The vehicle was not repaired. The manufacturer was made aware of the failures and provided a case number. The failure mileage was 170,000.

- Knoxville, TN, USA

The stability control/traction will activate for no reason thus slowing the vehicle down at freeways speeds. Mechanics find no problems with parts associated with issue.

- Reno, NV, USA

October 2016 this problem of my 2008 Toyota Sienna started- on slight curves doing 30-40mph I would hear a clicking noise coming somewhere underneath the front right end almost as if under the dash, the vsc light would flash. I took to a Toyota dealership, had a mechanic test drive with me they said the problem was that my tires werent aligned with my last tire change(which was done at their Toyota dealership) Toyota told me I needed to replace all the tires and have the wheels aligned. I did this, problem continued. I took my van in again to Toyota, they lied and told me I needed new brakes, and some other things I didnt need. Decided to get a 2nd opinion from 2 other auto shops and found out Toyota lied about the brakes, they were fine and they both were unable to find out my problem. I found this out going to 2 other auto shops asking for them to look into the original problem. Now today May 2019 this problem still exists, but has gotten worse. Now-the vsc light comes on, it still clicks, the ABS light and warning sound goes off, feels as if ABS engages, as it jerks and im unable to accelerate during this time until im on a straight away. Very scary when it happens the van starts jerking and unable to acelerate, not safe to take my family in. Never buy another Toyota again...

- Sun Prairie, WI, USA

When turning corners, the vsc light turns on, the car beeps, and the ABS system engages, causing the car to brake on own. This happens every day, intermittently, at all speeds.

- Gallatin, TN, USA

While driving the vehicle at higher speeds (greater than 40 mph) around curves, the skid indicator sensor will occasionally trigger even on dry pavement where no slipping is happening. The car will automatically decelerate and brake momentarily. There is often a clicking sound in the steering column as well. The vsc warning light occasionally comes on too. Mechanics on multiple occasions have not been able to figure out what is causing the problem. However, based on research at Toyota blogs, it appears that other Toyota Sienna drivers have experienced this same issue.

- Ashburn, VA, USA

The traction control system comes on when going into any right turn. The alarm beeps and the car automatically brakes, and the gas pedal is disabled so that you can not speed up. The braking can be so severe that it will reduce speed from 45 mph to 25 mph without notice which jerks the passengers violently.

- Vista, CA, USA