Two problems related to automatic transmission park/neutral start switch have been reported for the 2000 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2000 Toyota Sienna based on all problems reported for the 2000 Sienna.
Vehicle transmission was in park, the engine was not running, the key was in the ignition, the parking brake was not set, and nobody was in/near the vehicle. The vehicle was parked on a very mild decline on cement/asphalt surface. Vehicle rolled backwards, dropped off an 18" ledge and came to rest against a storage shed, which the vehicle pushed back about 5'. Vehcile was taken to dealer where 2 men tried to physically push the vehicle with no luck.
While vehicle was in park position and key was in ignition vehicle went out of park into reverse, and van ran into a tree before coming to a stop. Contacted dealer, and dealer was not willing to do anything.