One problem related to wiring has 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.
Spontaneous failure of electrical system involving brakes. At 43560 miles, the brake electrical has shorted causing failure of the gear release and all brake lights. Fuses instantaneously blow once brakes are applied. Lights and body wiring are ok, the failure seems to be in the ribbon wiring harness. Brake functions remain, no brake lights (potential accident).