2021 Prius. A little later this year I have to go overseas for three months. I can (1) park the car up and disconnect 12V battery or (2) have someone go to the car once a week and put in Ready Mode for 30 minutes or so (so it runs the engine and charges 12V battery). Which is the best option? Ideally I'd have someone use the car regularly, but got nobody who will do that......
running it is better, but sometimes people forget. i would park it with a fairly full battery, disconnect the 12v or put a maintainer on it, and pump up the tyres to prevent flat spots
Since the battery is easy to get to on this one. Put a smart RV battery maintainer on it and wrap the power cord around your driver's side mirror - do you don't forget to disconnect it when you get back. If you don't have a smart RV battery maintainer, just disconnect the negative battery cable on the car. Once you do that, the FOB and alarms won't work. You'll need to use the aux. key to lock and unlock the car. Hope this helps.....
I'd disconnect the 12V Neg terminal as advised. Then wrap it in a rag to prevent contact with any metal parts under the hood. I wouldn't trust anyone to run the car. I'd also practice using the metal/backup key in the fob to lock/unlock the car before finally locking her up after disconnecting the Neg terminal.
Many thanks for all the suggestions. Decided to leave the battery connected and get a Noco maintainer for it. That way someone can just unhook the maintainer and the can be driven away in an emergency.
Don't forget to wrap the power cord around the drivers side mirror; so someone doesn't take-off with the car plugged in... Also check battery electrolyte levels when you get back - to make sure that charger didn't boil-out all the electrolyte. It shouldn't but you won't know that it malfunctioned when you were gone. Hope this helps.....
I'll also be parking my 2021 Prius Limited for a couple months soon. If the battery is disconnected does one lose anything more than radio presets?
Yes, it possible. The car may also run/drive funny for a bit as the ECU relearns the proper engine calibration points. It all depends on what's being stored in volatile vs static/EEPROM memory. You can't reset your odometer this way!
When I've done 12 volt battery disconnects (typically for brake work), there's definitely an odd rev-up when starting, for the next few start-ups. There's also something odd first time you get in, push start. There's some mention in the Owner's Manual about that, forget what exactly. You'll also lose trip meters. You might need to reteach the auto-up on the windows. Not hard to do. Display will revert to how it was when the car was new, the graphic of car with energy going this way and that. That's about it I think.
