2010 II keeps dying even with new 12V battery - "park on level ground"

welcome!
two possibilities: the battery was not charged when installed, and has not been driven enough to charge it, or, you don't drive often enough to keep it charged.
3) something is draining it.

the 12v battery is charged by the hybrid battery, by way of the inverter/converter.

 

nothing normal. you would have to put some type of meter on it to see what the draw is with power off and on, and get the spec from the service manual.

any aftermarket electrical/electronics? alarm, remote starter, stereo/amp, etc.?

 

If you have a digital multimeter with milliamperes scale, you can patch it into the circuit in series, with the car completely shut down and quiet, see how much load there is. Doing this I found 15-20 milliamperes with occasional spikes to 40.

You disconnect neg battery cable, connect to meter, and meter to battery. Start on amps setting, then switch to milliamperes if no reaction, just to play it safe.

The clamp-on style ammeters are simpler I think: no need to splice in meter.

 

1. Check the battery cable tightness at the battery.
2. Check the negative battery cable tightness where it is bolted to the body.
3. Measure the voltage across the battery first thing in the morning, before the car has been driven, and report your findings.

 

The most common clamp-on pickups, though, are only good for AC (which can induce its own voltage in a surrounding coil). To measure DC takes the less common, powered, Hall-effect style of clamp. I've got one, but it's kind of an industrial gadget sized for large currents. Anything smaller than about 4 amps tends to be hard to measure with any certainty, though sometimes I get a little closer by clamping it both ways and averaging the readings.

So for the kind of small currents you're looking for in parasitic drains, it really works best to insert the meter in the circuit.

One handy tool I found for that is the "Fuse Buddy", and I picked one up recently:



Disappointingly, I found its wide shoulders (just above the mini-fuse-sized snoot) won't let me get it into the fuse slot I needed, because of a bracket Toyota stuck right next to the fuse box. But I took the Fuse Buddy apart and it looks like there's enough room to trim those shoulders some (then cover with Plasti Dip for insulation) and see if I can make it fit.

-Chap

 

Look up a youtube video for how to check parasitic draws/drains. Also, take the battery by an autopart shop to have it tested. Sometimes new batteries fail, that's why there are warranties.

 

good point. might as well make sure the battery is healthy first. a simple fix, compared to trying to find a parasitic drain.

 

Also, while you're checking for tight connections, make sure there isn't any corrosion, especially where negatives connect to body or other steel parts such as the negative wire off the battery to the body.

 

Also measure it after the car has been started.
If the second reading is not considerably more than the first.......at least a volt higher.....then your 12 V converter has failed.

 

Actually, that's a good indication of a loose connection. And rough roads can loosen a connection if it wasn't tight enough to begin with. In fact, they'll do far worse than that. Nine years of driving in Honduras taught me all about that!

 

Look up the definition of "intermittent".
It's quite common with electrical things.

But you still need a meter to check the voltage, partly because the intermittent connection could be INSIDE the battery itself.

 

Thanks for the thread. I had a similar issue with my 2010 Prius (purchased May 2010)

I had an issue where it was basically dead at a parking garage and gave a tone error for long period and was un responsive. Gave error about being parked on un-even surface .... I tried jumping the car to no avail and was going to have it towed home. Guy came and jumped it (I had to show him how to do it since never jumped a Prius before) and it started up very quickly for him.

We drove all the way home with no issue except some of the console wout not read out properly.

Put it on a cheap charger that night and worked great.

Yesterday morning same deal, but no time to fool with it so took backup car and dealt with it last night. Battery was dead so I charged it and it finally got charged late last night enough but now getting the message to use park and message won't go out.

Hopefully will get the thing so I can get it to a dealer and don't have to have it towed.