How to save battery when on vacation?

There have been several threads about people going on vacation, getting deployed, etc. and needing to store their not-in-use Prius for extended periods of time. I can't locate any of those threads at the moment, but it was suggested (and I believe it also says so in the manual) that if you plan on leaving your Prius alone for an extended period of time, say more than a week, you should disable the SE/SS (Smart Key) system by toggling the switch under the steering column. This will help prevent battery drain.

 

Here's one of the threads I was looking for. The ones I'm thinking about were created well over a year ago, and I haven't come across them yet.

http://priuschat.com/index.php?showtopic=15076

As with most cars, the occasional use/startup falls under the "proper care and feeding of your Prius" guidelines. I've let my 2005 Prius sit unused for a couple weeks without issue, but that's about the longest period of non-use mine has seen.

 

I was in Gulf Port, Ms. doing hurricane relief work for 3 weeks and had no problem starting my Prius when I got home.

 

Twice I have left my 2004 unattended for six weeks in the winter. I disabled the SE/SS. Both times the car was fine when I returned.

 

How long was it parked when you found the battery dead?

The headlights DO shut off automatically when you open the driver's door, BTW. Many people leave the light in the "on" position all the time.

We're talking about the AUX battery here, and there's nothing magical about the Prius in this regard. Like in all other cars, wants to be kept charged. One easy solution (for vacations, etc) is to hook up a smart little charger to it to keep it topped up. The worst thing you can do for a lead-acid battery is let it sit. They love nothing more than to be charged constantly.

For sure you should disable the SKS when the car is left for a long period.

 

<div class='quotetop'>QUOTE(ladykira @ Jun 6 2006, 09:45 PM) [snapback]267103[/snapback]</div>

Nobody thinks you're dumb. We're just trying to figure out how best to help!

The car should have NO problem sitting for a couple of weeks, much less two days. If your battery is going dead after just two days of sitting, something is most definitely wront. Either with the battery, or with something draining it!

My 2006 Prius is only driven once ever two weeks or so. I haven't had a single issue with it not starting.

 

If it happens again ask the dealer if they checked the charging system and the battery. They need to do both. They most likely did but it won't hurt to ask because sometimes they overlook the obvious. Make sure you don't have an interior light or something that's staying on when it shouldn't.

The Prius aux battery (thats the 12 Volt one that went dead) really isn't very big because it doesn't start the engine or anything. It's about the size of a motorcycle or lawn mower battery so even an interior light can run it down in a day or less.

I don't think it would be anything environmental. The climate where you live is pretty easy on batteries and I can't think of anything else external to the vehicle that would cause the problem.

 

<div class='quotetop'>QUOTE(ladykira @ Jun 7 2006, 12:58 AM) [snapback]267107[/snapback]</div>

I think the dealer just doesn't know what else to say. 2-3 times a week is more than enough. Even once a week as long as it's more than a 5 minute trip would be enough. Thinking about that, how long do you drive it during the 2-3 times per week?

 

Ditto Evan. It's easy to leave the hatch not-completely-closed, and the trunk light does not turn itself off.

Always lock the car; if anything is left open the car complains about it as a reminder.

 

<div class='quotetop'>QUOTE(darelldd @ Jun 7 2006, 12:05 AM) [snapback]267082[/snapback]</div>

Agreed. What you need is a "Float Charger", not a regular, manual battery charger. A regular charger will overcharge the battery, and eventually kill it. I bought a really nice float charger at Harbor Freight. It is normally $20, but, like everything else at Harbor Freight, it was on sale for half that.
I use it on my ex-daily driver, which has an Optima Red Top that insists on going dead if I don't drive the car at least once a week.
The Harbor Freight one has two big battery clamps. You will need to pop the hood, open the fuse box, and clip the + lead onto that jump starting terminal in there, and put the - onto a good metal ground. If this is an ongoing issue, I would think about making up a quick-disconnect for it.