One problem related to speed control springs has 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.
Failure of the adaptive cruise control module on a 2006 Toyota Sienna xle limited. The adaptive cruise control module, located under the front bumper on the passenger side, fails completely and continuously resulting in complete failure of the cruise control system. The module is not sealed properly thereby allowing moisture inside resulting in corrosion and failure of the part. When actuated, the part is designed to automatically slow the vehicle while approaching slower traffic from behind. Failure of this part while driving could result in an accident if the module does not automatically slow the vehicle properly. The vehicle in question has only 21,000 miles on it. The failure occurred at approximately 15,000 miles. Toyota of colorado springs replaced the part at cost to the owner of the vehicle.