[Templeton]

Thanks for all of these posts. It seems to exactly describe the issue I had.

We have a 2022 Sienna platinum with 2560 miles on it. I went to get into the van and start it but and I received parking brake unavailable messages on the display, interior lights were dim and the van would not start. The van was last driven 6 days before in a snowstorm and then was parked in the garage where all of the snow melted off. The garage was 40+ degrees Fahrenheit so the van was in a warmer place.

After reading the posts I also determined that the 12 volt battery was depleted and then used a plugin battery charger for 5 to 7 mins to recharge the battery (instructions are in the owners manual) and then tried to start it up. It started fine, I disconnected the charger and then drove around the neighborhood for 20 mins and then disabled the hands free door sensors for the sliding doors and the lift gate.

I'm going to pickup a portable charger just to keep one in the van in case this issue happens again.

I'll try to update this post going forward. If this fix resolves the issue for me or not.

Not sure if this will also help, but we have a 15 year old prius with an old 12v battery and with smart keys (but no kick sensors) that we park outside. On very cold nights (below freezing or colder), we disable the smart key system (small button on the lower dash makes that easy). We noticed that, in extreme cold, the smart key system would also drain the old 12v battery (since the prius and sienna has a smart key radio receiver that runs on the 12v system and is powered on 24/7). So that might be something to do for the Sienna to preserve its 12v battery as well.