We will skip right over the first-generation model, as those were the best Sienna years. Instead, we’re kicking off with the first model year of the second generation. It’s the model year with the most reported issues, which isn’t odd. No matter how much testing a company does, the worst models are usually the first batch. Generally, an automaker takes a year or two to iron out the kinks.
For the 2004 model year, the NHTSA received 2,054 complaints, leading to 10 investigations and 10 recalls. These recalls fixed several major defects but not the thing owners complained about the most.
Owners of 2004 models complained the most about the sliding doors, a used minivan must. The reported issues are for both the standard and power sliding doors. Malfunctioning sliding doors are extremely dangerous, and there’s a real possibility that somebody (a toddler) could get seriously hurt.
There isn’t one specific problem, but rather a series of power door issues. Almost all of the complaints are about shoddy welding and poor design. Various spot welds can fail, but the latch that holds the door open is the most concerning.
Another issue to look out for is a cracking dashboard. According to owners, the cracks in the dashboard started forming after roughly five years. In some cases, the cracks got bad enough to interfere with the air conditioning system. A few owners also said their radios eventually stopped working because of the cracks.
