Dead battery after 2.5 weeks

<div class='quotetop'>QUOTE(jonbeck @ May 23 2007, 04:02 PM) [snapback]448479[/snapback]</div>

You've probably already thought of this, but you don't think you pressed the button NEXT TO the SKS button, do you? Isn't the tire pressure warning reset button right there, too? Maybe that's the one you pushed and only thought you'd turned off the SKS...?

I'm not an expert, but I also do recall hearing about the JBL audio amp draining the battery; something about an internal fault increasing the amout of dark current (that's a term, isn't it?) which is taken from the battery, even when the car's off.

Only things I can think of right now...I'll bet that the PC 'brains' can tell you more!

 

Door ajar, car alarm, SKS on, faulty electronics (such as the JBL amp), or just a plain bad battery.

Tom

 

Pinto girl I think you are talking about a "phantom load" maybe

 

<div class='quotetop'>QUOTE(priussoris @ May 23 2007, 06:59 PM) [snapback]448583[/snapback]</div>

Thank you!

"Dark Current" sounds like a vampire drama that used to be televised on Saturday afternoons!
[laughing]

 

Well, batteries generally don't take kindly to being fully drained. Do it once and it's not likely they will ever regain their original capacity. It could be that it didn't fully recover from the first discharge and the normal electrical load (minus SKS) was too much for it the second time.

You might want to look into quick disconnects for the battery. It's kind of silly since it's not that hard to pull the cable, but you might find it more convenient to pull a simple knob instead. This is what I'm thinking of. Worth $5?

Of course, then you need to get into the hatch to get at the battery when the fob doesn't work...

 

Parasitic loads, in fact, are fairly *easy* to diagnose. You drop
an ammeter in series, and then start isolating stuff until the drain
goes away, and do as close to binary-search as you can by pulling
major interconnects and likely fuses.
.
_H*

 

<div class='quotetop'>QUOTE(jonbeck @ May 23 2007, 03:02 PM) [snapback]448479[/snapback]</div>

Trunk light on? First Prius I test drove, we walked out to the parking lot and the Prius we drove had the trunk not closed all the way. I think the Prius trunk needs to be closed forcefully. This may or may not mean the trunk light was on, but I would check interior lights first.

 

<div class='quotetop'>QUOTE(jonbeck @ May 23 2007, 05:02 PM) [snapback]448479[/snapback]</div>

I hate to get picky here, but the tiny 12 vdc battery is an "auxillary" battery, not the "starter" battery. If your primary NiMH 208 vdc "starter" battery went dead, you'd need one of a handful of specialized Toyota Traction Battery chargers in the country. Or you would have to make your own charger.

I use a VDC Battery Minder on my 12 vdc battery, as I'm frequently away on business. A search of this forum with my user name and "battery" should bring up the details. It keeps the battery "conditioned" by removing sulfate deposits that can form if a battery is chronically undercharged.

As Hobbit mentioned, it's very easy to find parasitic loads with an ammeter in series. My Prius resting current is around 28 mA. I haven't hooked up the AEMC recording power meter from work yet, since I'm curious to determine how often the brake booster pump runs.

Around a year ago I was in the underground parking and I heard the pump briefly run. If it runs often enough, after a couple of weeks or a month, the battery is dead.

 

<div class='quotetop'>QUOTE(hobbit @ May 23 2007, 11:09 PM) [snapback]448701[/snapback]</div>

Another factor in addition to all this is the question of how well charged your 12 V battery is before you leave it and it gets run down. Different useage patterns may mean that you are not starting off with a fully charged battery before the 2 1/2 week hiatus. A load test on the battery could answer that as well as address any concern that the battery was damaged by the previous dead battery incidents.

- Tom

 

<div class='quotetop'>QUOTE(jonbeck @ May 23 2007, 08:23 PM) [snapback]448599[/snapback]</div>

I bet that's it. The DICE is powered at all times, even when the car is turned off. At least my wife's Dension ICE>Link is.

 

<div class='quotetop'>QUOTE(jonbeck @ May 24 2007, 03:59 PM) [snapback]449292[/snapback]</div>

Because the damn thing (the ICE>Link that is) keeps locking up and the only way to reset it is to unplug it from the radio and plug it back in. When I do this, it displays a message that it only displays when you first plug it in. I eventually used a multimeter to figure out which wire is the power line and I put a push button switch in the circuit so I can cycle the power to reset it.

Also, the ICE>Link (and probably the DICE) has a feature that allows it to charge your iPod for a configurable amount of time after you turn off the car. It could only do that if it is still receiving power from the car.

 

If you still have the original battery, now twice drained, replace it. It'll never be the same, and it will fail you at a most inconvenient time.

 

<div class='quotetop'>QUOTE(jonbeck @ May 24 2007, 04:38 PM) [snapback]449376[/snapback]</div>

I would get the battery load tested it may or may not have a bad cell. It wouldn't need replaced just because
it was drained down.

 

If the 12 vdc auxillary battery has been chronically undercharged/discharged, it will no longer hold a full charge with "conventional" battery charging, due to heavy sulfation of the battery plates. A battery charger that claims to "desulfate"can usually restore a 12 vdc battery to full capacity, if used in time.

I managed to pick up 3 of the previous generation VDC Battery Minder at an auction place several years ago. Not sure if I would pay $70 for one, but I guess compared to the replacement cost of a new Prius 12 vdc battery, it's still cheap.

http://www.vdcelectronics.com/batteryminder_12117.htm

I have the hardwire harness hooked up to my Prius and my FJ, as I'm frequently away on business. I leave the Battery Minders on all the time, even just overnight with the Prius, and the batteries are still strong. The hardwire harness is a bit of a PITA to hook up in the Prius, these photos prove it.

Note: that very tiny negative ground wire has been suspected of causing some weird electrical issues. Anytime you have a corroded ground, you can expect odd electrical behavior. I back off and tighten the battery ground at the unitbody every fall and every spring, to ensure a good electrical ground.

 

<div class='quotetop'>QUOTE(jonbeck @ May 24 2007, 06:11 PM) [snapback]449424[/snapback]</div>

AFAIK there are no direct non-Toyota drop-in replacements. There are others that will fit, but I don't know them.