Two problems related to brake disc pads have been reported for the 2006 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2006 Toyota Sienna based on all problems reported for the 2006 Sienna.
The slip indicator light (car with swerve lines) started coming on intermittently while turning on highways etc. (but not when any risk of tire slipping). Then vsc light also came on and alarm sometimes sounded. Visit to our own mechanic, no problems found. In the last 2 years the abs system has activated (daily) it unexpectedly applies the brakes while in motion. It is on specific types of curve and while driving at least 30mph, but has done at 35, 55, 70 mph, on slight or medium turns (not real sharp turns), going uphill or downhill and left or right. Took my mechanic for a ride with the diagnostic computer hooked up, it did the abs braking, warning light, and beeping 5 times but computer showed no codes. Suggested resetting yaw which we did, it did not help. Suggested calling Toyota, they were no help, said they had never heard of that problem and my mechanic probably did not know how to read the computer. When abs activates it's very dangerous - thinking about deactivating entire vsc system. I believe the rack and pinion may play a role, there are rattle and bump sounds, perhaps a loose suspension is the culprit, that is our next option. I have already replaced struts, front wheel bearings, all new tires, had it aligned, did new brake pads, and rotors. Absolutely fed up with this problem!.
Front brake pads wore out very fast. Front brakes make noise, 3 times fixed under waranty and 4th time being fixed at dealership under waranty. I think some problem with brake system design and function.