Three problems related to seats have been reported for the 2005 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Toyota Sienna based on all problems reported for the 2005 Sienna.
Passenger seat warmer was on the other day while I was driving and began smoking and melted the seat in the shape of a dime. For a couple weeks it was causing burning feeling in legs from being too hot. I turned off seat warmer and hit the seat until the smoking stopped.
I was completely stopped in my Sienna awd at a traffic light at the top of a freeway on-ramp in a major city, and rear-ended by a vehicle beginning to travel down the on-ramp at an unknown but high rate of speed and not heeding the traffic signal. On impact, the rear cargo compartment of my Sienna crushed inward so far that it caused the third row bench seat to move forward and propel the seat part of the bench seat into the backs of the second row captain's chairs in front of it. This would have crushed the legs and maybe whole body of anyone seated in the outer two seats of the rear bench seat, and perhaps in the middle position as well. I found a piece of paper bag caught between the bottom seat edge of the bench seat and the back of a captain's chair, and I could not pull that piece of paper free. I had to pull really hard to remove the large pack of toilet tissue, shown in the uploaded photo, in order to dislodge it from the rear bench seat area. The tissue pack likely is narrower than the trunk of an adult human body which could have been caught there, with legs also crushed by the lower portion of the bench seat as it impacted the back of the captain's chair in front of it. I believe the cause of this safety problem is a poor design; inadequate rear-crash protection for third-row passengers, who usually are children. As a parent and vehicle owner, I was never warned about the great danger my children could be in if they seated anywhere along the third-row bench seat during a rear-end collision. I'm traumatized by the thought of a child or anyone having been seated in the third row at the time of this collision, which fortunately they were not in this instance.
Seat warmer on drivers side burns my leg if left on for more than 2-4 minutes. Understand there is a recall for this year and model but was told by Toyota the recall does not apply to factory installed models(xle) , which mine is, only vehicles which had seat warmers installed by southeast Toyota(set) as an option.