37 problems related to electrical system have been reported for the 2015 Toyota Sienna. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2015 Toyota Sienna based on all problems reported for the 2015 Sienna.
The speedometer & tachometer on the model has a dark background with small numbers and doesn't illuminate in the auto position. If the sun is bright with glare off other vehicles and you have to wear sun glasses they illuminate but the are either difficult to see or impossible. This is a safety concern, in my opinion, while you vehicle is in motion.
I have a 2015 Toyota Sienna xle with 35,800 miles. - (no specific conditions or driving styles) it is on it's third transmission (second replacement was at 29,800 miles) - newest recall on the side doors opening randomly. - (no specific conditions or driving styles. Happens completely randomly) cruise control lever light flickering. It was replaced three times now. It was just replaced the third time recently, so I'll see if it happens again. - (no specific conditions or driving styles. Happens completely randomly) dash randomly freezes for about 5 minutes and then resets to the default settings (it has happened seven times and continuing) and Toyota still cannot figure out the problem. - (while driving on a clear day on a city street) climate control shut off completely by itself without touching any buttons while driving. I was able to turn it back on, but it should not shut off without any action. - bad support bearing for axle on front passenger side (22,900 miles).