One problem related to alternator/generator/regulator 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.
Driver's side power window stopped working. Mileage approx. 126,123. Toyota dealer said window regulator assembly and motor needed to be replaced. I specifically asked if the master power window switch was involved, because Toyota just sent out recall 15v689000 saying the master power window switch in some Toyota vehicles could melt or overheat. Toyota assured me that no, the switch was not involved. I took the van to another shop for repair. They replaced the window regulator assembly and motor, as per Toyota diagnosis. The window still did not work! and when the master switch was depressed, the control panel began to visibly smoke! to further test, the shop supplied separate power to my original window regulator assembly and motor - and they worked fine. The shop then re-installed my original window regulator assembly and motor, and replaced the master switch. The window now works. Toyota clearly missed the boat on this one. The switch failed and the fact that it visibly smoked means that it does, indeed, fall under the recall. This repair should be covered or reimbursed under the Toyota recall. And yes, the Sienna is affected.