2006 Prius I got on March 1 is....

<div class='quotetop'>QUOTE(supernole1 @ Apr 3 2006, 01:50 PM) [snapback]234336[/snapback]</div>

Where are you located?? From what I've read here, temps can have a lot to do with battery charge. I got mine on the first of March as well and I can tell you that in L.A. I don't see anything like that. Might be time to take her into the dealer to get it checked out.

 

<div class='quotetop'>QUOTE(supernole1 @ Apr 3 2006, 04:50 PM) [snapback]234336[/snapback]</div>

How cold is it? I know my Civic Hybrid neither uses the motor nor charges the battery until the battery is within a certain temperature range, to prolong its life. Maybe if it's really cold where you are, the Prius won't use the battery until the car warms up a bit?

 

<div class='quotetop'>QUOTE(supernole1 @ Apr 3 2006, 05:50 PM) [snapback]234336[/snapback]</div>

Hi Supernole1,

It almost sounds like you are leaving the car on. Say, in drive, with the parking break on, or in park with the AC on. Also, if you leave the hatch incompletely latched, that will leave the interior lights on. Which may then run down the battery. Although there would probably have to be some more drain that that to bring the main battery so low. The rear hatch being aluminum is somewhat underweight for the gas springs, and one has to really close it hard.

Do you have the Smart Key System? I cannot help you with that.

Make sure you hit the "POWER" button to turn off the car.

 

If you're saying you parked it last night with 75% charge and this morning it shows something like 15% charge -- I'd say arrange a visit to the dealer ASAP. This baby needs looking at right now.

 

You do not indicate what package you have and whether you have the Smart Key System. If you have SKS you need to worry about where you store your fobs...if you store them within 15 feet (3 meters) of the car at all times you can run down the battery.

If you don't have the SKS and you are actually turning off the car (and not leaving it in ACC), then follow other folks advice and take it in!

 

i'd guess the car is being left on overnight.

the car backs up by running the electric motor backward, which requires the HV battery. that explains the reverse problem. now the questions turns to the battery.

make absolutely sure the car is off when you leave it. if the car is off, then something's up with the battery control system. however, you should be seeing some kind of light on the dash to indicate a problem... which is why it sounds to me like the car isn't being turned off at night.

best thing you can do is to take notes about this in case you need to take it in. note the following:
time of day car was parked
temperature
bars on battery meter
mpg reading
time of day car was restarted
temperature
bars on battery meter
mpg reading
along with any other things you feel may be important.

 

Sounds like a fault to me. As long as the car is turned off (or even in ACC or IG-ON modes, where the READY indicator isn't lit), the high voltage battery is disconnected by a couple of big relays. You can hear them go clunk-clunk in the back when you stop and start the car. Thus whatever you do with leaving lights on etc can't affect the main battery; at worst you can drain the 12V one, thus requiring a jump start.

There should not be any appreciable overnight drop in indicated charge level - at most you might see it 1 bar lower in the morning occasionally.

If it really is acting as if the HV battery pack is draining overnight, you've either got a battery fault or some sort of sensor problem in the battery management system. So take it back under warranty pronto - it may be an expensive fix, but make sure you're not paying.

 

<div class='quotetop'>QUOTE(efusco @ Apr 3 2006, 09:23 PM) [snapback]234438[/snapback]</div>

Really? I just assumed you need to put the car in park before turning it off. With any other car, you would never turn off the ignition in drive.

My feeling on the subject is that it takes virtually no effort to press Park before powering down, so why chance it?

 

<div class='quotetop'>QUOTE(efusco @ Apr 4 2006, 09:23 AM) [snapback]234633[/snapback]</div>

I stand corrected.

OK, so here's a follow up question: With other cars you are supposed to wait about 10 seconds after you start before driving (I guees for the oil and other fluids to get going). I know you don't need an extended time for the Prius to warm up, but do you wait at all, or just press and drive?

 

Press and drive. It is a good idea to be gentle for the first few minutes until everything warms up, but sitting for any length of time with it "Ready" and not moving just wastes gas.

 

I left a light on in my car overnight this past weekend. When I started up the next morning I was down to one pink bar. It took 5-10 minutes for the blue bars to show up.