Storing car, how often does it need to be started?

I've read other posts that indicate pushing the button under the steering wheel to turn off the SmartKey resolves this problem when stored, at least for a while. But I'm not sure how long that would be good for. The answer from more knowledgeable members will be interesting.

 

Get a solar panel type of battery tender. It is necessary to give the 12V some sort of boost, and desulfation pulse if possible.

 

Hi Kevin,

If your wife is not going to drive the car and it will sit unused, I suggest that you first fully charge up the 12V battery in preparation for the car's storage. Then, disconnect the battery via the following process.

Open the hood and remove the lid on the main relay/fuse box near the inverter. Press hard on the latch on front of the lid, then pivot the lid up.

Find the dedicated positive jump start terminal covered by the red plastic cover. Open the cover.

Use a 10 mm socket to remove the nut on the stud there. Then use long-nose pliers to pull up the cable attached to the stud. Replace the nut, replace the red plastic cover, let the cable sit on top of the red cover, close the relay/fuse lid, close the hood, lock the car and you are done. Your wife will not have to do anything to the car.

When you return from your trip, reinstall the cable, charge the 12V battery, and the car should be ready to be driven.

Note that making the Prius READY for five minutes weekly does nothing to help the battery and probably leaves the battery worse off than if you had done nothing - because the drain on the battery from powering up the ECUs may be greater than the charge received over a 5 minute period. If you want to periodically charge the battery via making the car READY, the car should be left READY overnight (i.e., for an 8 hour period) monthly.

If your car is going to be unused more than 2-3 months then the high voltage traction battery is under some risk of being discharged. Force charge the battery to 7-8 green bars before you put the car in storage, then hopefully you will be good for 6 months. If your storage is longer than that then you will need your wife to make the Prius READY overnight, monthly, to keep the 12V and high voltage batteries in good condition.

To force charge the traction battery, make the Prius READY, shift to D, press hard on the brake pedal with your left foot so the car remains stationary, floor the accelerator pedal with your right foot, and watch the traction battery SOC gauge on the MFD. As the charge level rises, you will note the engine RPM will automatically decrease. This may overheat the transaxle so performance of this procedure is at your risk. Do not overdo this process.

 

Maybe post how long you're going to be gone, will help responders.

 

I wonder if there is a Gen 2 version of the TSB at 2010 II 12 Volt Battery Dead After 17 Days of Parking | PriusChat.

 

If you fully-charge the 12V battery before you leave, then I would say that if your wife starts the Prius 2x per month, and leaves it READY for four hours at a time, that will do a good job of keeping both batteries in good condition. I don't know what condition your 12V battery is in and how much capacity it has, so my advice is geared towards the conservative side.

A 30 minute period might be adequate for the traction battery but is not adequate for the 12V battery. Obviously, this will require you to fill the gas tank before you leave so that your wife does not have to worry about the car running out of fuel while you are gone for six months. Good luck.

 

Easiest solution for 6 months is: just let your wife use the Prius. ( when you return, she may not release the car back to you, tho )

 

The HV battery will easily manage a 6 month period without charge providing it is at the five blue or six green bar level when first left. The twelve volt battery should be taken off the car and put on an auto battery tender for the period your away.

 

This is always the best solution, if possible. Cars like to be used, and it doesn't have to be daily: a couple of times a week, or once a week will do. We've done that for relations. I usually end up completely detailing the vehicle too, LOL.