The trac control is activated while the car is driving variable speed and brake the car and and the driver loose control of acceleration.

- Saratoga Springs, UT, USA

- Traction control engaged at high speed(70 mph on interstate) causing the vehicle to brake abruptly and pull the vehicle to the right. Had I been traveling in the left hand lane, I could have been forced into the right hand lane causing a collusion with another vehicle. Also occurred at lower speed(30 mph on a windy road) causing the same issue as described above, almost causing the vehicle to leave the paved surface. - Mechanic was able to duplicate the issue - Mechanic diagnosed intermittent traction control activation, scanned computer for codes. Yaw rate/steering angle correlation causing false activation ABS/traction. Replaced hub bearing and spindle. Four wheel alignment, including check castor, camber and adjust toe. Performed zero point calibration and reset ABS memory. - Traction control lights up briefly

- Fletcher, NC, USA

About a year ago the Vehicle Stability Control warning light along with an audible alarm started coming on intermittently while turning on highways going uphill or downhill in dry weather and with no risk of any tire slipping. At first this only happened at higher speeds 65+mph. Over time, it has occurred more and more frequently and can occur at speeds down to 25 mph. At times, the Anti-lock Braking System is also activated resulting in jerky braking and loss of throttle. When people have been following me too closely, this has almost caused accidents. When these symptoms occur, it is always on a curve (of any degree, even slight curves) and while driving at least 25 mph, and even happens on flat turns now. The weather has always been dry with no risk of tire slippage.

- Simi Valley, CA, USA

The failing component is the VSC/ABS system. It puts the occupants of the van and other motorists at risk of either causing a collision or causing the driver of vehicle in question to be unable to control the vehicle. The failure appears when going in a curve in the road at low speed causing the abs to engage lock the brakes and steering wheel rapidly decelerating the car and causing the car to jerk to one side or the other and go into a skid where the driver is unable to control the wheel due to steering wheel locking up when it happens the VSC and TRAC lights come on and there is a loud and rapid beeping that can be heard inside the vehicle. The issue usually appear when going between 25-40mph in banking curves

- Chesterfield, VA, USA

Sometimes when I take turns in my Sienna, the VSC starts going off and braking individual wheels without my control. This happens unexpectedly on highway bends at speeds of 60+ mph and it is difficult to control the car and keep from swerving into another lane. If the roads were icy when this happens, it would probably cause a dangerous accident. Toyota has a technical service bulletin for this, but not a recall - which it should since this is a significant safety issue. The TSB is BR008-04. There are many others experiencing this same issue: https://forums.edmunds.com/discussion/13855/toyota/sienna/vsc-sudden-activation-2004-toyota-sienna

- Lakewood, CO, USA

While driving on dry freeway or other stable road conditions, the Electronic Stability Control kicks in, braked hard, causing the van to swerve, and the lights on the dash started flashing, accompanied by a loud beeping. This has happened multiple times now. There is no reason for this to be occurring. It is involuntary, sudden, and random. If someone were close behind me, they could rear-end the vehicle. It also sometimes pulls the steering so hard that it swerves into the other lane. This is a serious safety issue that Toyota needs to deal with.

- Pullman, WA, USA

Numerous times (too many to say), the traction control indicator sensor comes on & I am unable to control the car. Typically it lasts for 2-3 minutes and turns off. It does not depend on road conditions, weather, and or speed. I have taken the car to the repair shop and they have not been able to capture anything on the engine diagnostic system. No codes were found for them to troubleshoot this issue. I've seen this problem being reported on several posts. Yet the NHSTA has done NOTHING!! TOYOTA NEEDS TO BE HELD LIABLE FOR THIS ISSUE. WAKE UP NHSTA. MAKE OUR TAX DOLLARS WORK!!! This poses a huge risk to my family and other drivers, not to mention impact on budget.

- Hockessin, DE, USA

ABS some times activates when driving a light curve road at speed around 30-40 mph. Usually a steering wheel is about 2 or 10 O'clock positions. At the time vsc indicator flashes and warning alarm goes off. This causes a sudden breaking and it becomes very difficult to control the car.

- Lawrenceville, GA, USA

The vsc system is enabling while driving and making a turn on an otherwise normal road. When it enables, it applies the brake and sounds a repeating alarm. The system applies the brake while I am attempting to make a turn, and this makes me feel unsafe, as if I have temporarily lost control of the vehicle while making an otherwise benign maneuver. The repeating alarm does not turn off until I have turned the wheel to the opposite direction from the initial turn angle. This means if the turn is slow, the alarm will sound for the entire distance of the turn.

- Stillwater, OK, USA

In motion, on dry, off-camber highway curves, with slight acceleration, the ABS/vsc /trak engages, briefly jerking the steering to one side. Dash warnings: "vsc" "trak off" + "check engine". reducing mechanical "slop" (wheel bearings, steering rack & pinion, etc.) tends to reduce frequency of occurrence. Toyota dealer diagnosis: "steering control system fault". >"Toyota knows about -- but, does not know how to fix this problem."< dealer-suggested workaround: "pull fuzes to disable vsc and ABS systems..." dealer repair documents are with previous owner...

- Bivins, TX, USA

This vehicle has a traction control feature which helps keep it from skidding out of control in icy, wet, or otherwise unstable conditions. It can help an out of control vehicle get back into control by doing a variety of things, including braking. Previously this feature had only kicked on when I would slide on the snow during a low speed turn and would slide in the snow (which was good). But over the past few months, there have been two times that this feature has kicked on at high speeds (once at 40mph and once at 65mph) on dry roads, both while turning around a curve. Suddenly the braking system is applied without any warning and the vehicle swerves slightly and does what it wants for a few seconds. Then it stops. If this were to happen on an icy road at those speeds, the vehicle could certainly spin out of control. The vehicle could also swerve into an oncoming lane of traffic. I have seen many forums online where other Sienna owners are having the same issue and Toyota dealers say they can't replicate or fix the issue. This is certainly a safety issue that needs to be looked into by Toyota to see what is causing this issue. Thank you!

- Great Falls, MT, USA

Driving at 50 mph on a two lane highway the car suddenly veered to the right and decelerated/braked hard, under it's own control, not mine.

- Eugene, OR, USA

When driving in dry conditions at various speeds over 25 mph, the vsc warning light comes on, an alarm sounds and the antilock brakes engage for no reason. This is a terrifying and extremely dangerous issue that is well documented by so many Toyota Sienna owners but to date has not been addressed or acknowledged by Toyota. When taken to a dealership, they claim (as other owners have also stated) that they cannot replicate the problem and it does not register through the obd2 sensor so there is no record of it happening. With as many people as this is happening with, it is not a question of whether there will be accidents, injuries and ultimately deaths caused by this issue. The only question is when and how many have to occur before Toyota acknowledges this is a problem. Driving down the road, in traffic at 65 miles an hour when for no reason, the car slams on the brakes without warning. It is happening all the time at this point making the car completely unsafe to drive for the owner, the vehicle's occupants and any unsuspecting vehicle in the vicinity. I am begging you. Please get Toyota to issue a recall before tragedy strikes. Thank you for your prompt attention to this matter. I am submitting the date below as today's date as the car is now sitting in my driveway until I can figure out what needs to be done. It has happened over the past 6 months every time I drive it and the $750 steering position sensor that Toyota replaced did nothing to address the problem.

- Summit, NJ, USA

Traction control malfunction. While driving on curvy roads there is a beeping alarm, steering locks up, brakes engage. The car seems to think that the traction is off. This has been a problem for over a year. No problems driving in city. Only happens on curvy roads.

- Seattle, WA, USA

Traction control kicks in for no reason, tration beeping and tires lock, at freway speed traction control activates and cuts off speed dramatically.very unsafe to drive.

- Santa Clara, CA, USA

When traveling at highway speeds and usually on a slight curve to the right, the traction control alarm and breaks go off causing the van to jerk and shake. We have been told this might be low tire pressure but the tires are fine. We have had an alignment, new tires this problem happens randomly and we have not been able to reproduce it for the mechanic. We have been dealing with this for a couple of years maybe happening 20 times. I feel it is just not safe enough to drive or pass this problem on to someone else. I wouldn't want the car on the road with me either I have read online of other Toyota Sienna's with the same exact problem. This is not isolated and is a safety concern.

- Elizabeth, CO, USA

The contact owns a 2004 Toyota Sienna. While driving approximately 50 mph, the traction control warning indicator illuminated and a warning chime sounded. The vehicle lost steering and braking ability, and the steering wheel started to jerk from left to right. The contact continued to drive and the failures went away after thirty seconds. The contact stated that the failures randomly started approximately one year ago and grew worse. The contact also mentioned that the lock on the sliding door showed that it was unlocked; however, no one could exit the vehicle when attempting to open the door from the inside or the outside. The vehicle was not taken to a dealer or an independent mechanic for diagnostic testing. The manufacturer was notified of the failures. The vehicle was not repaired. The approximate failure mileage was 150,000.

- Bensalem, PA, USA

I have experienced the issue with 2004 Sienna le with 130,500 miles. Traction control kicks in at 45-60 miles per hour on straightaway, clean pavement, no rain, no snow, and brakes car and cuts power. Almost lost control of vehicle when it happened, steering into other lanes. It happens frequently and is very possible to have the car rear ended if a car behind me is closing on as the speed suddenly slows down. Apparently this is a big issue that I found lot of other Sienna owners is sharing from the forum. As far as I know that many Toyota dealership is not intend to acknowledge such issue and able to fix them.

- W Hempstead, NY, USA

On freeway interchanges, entrances and exits vsc and ABS suddenly engagess. Van is not aggressively driven and when turning on mountain roads and switch backs vsc and ABS engages despite the slow and controled steering.

- San Lorenzo, CA, USA

When I am driving my 2004 Sienna, its shaking so badly I feel like wheels going to roll out. Also brake make worse, and engine mounts and transmission mount are very bad condition. I don't know why its bad breaking in rain.

- Irving, TX, USA