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At least in the 2004-2009 generation, leaving the light in the luggage area on was a common source of battery drain.
Also, given the Prius design, you shouldn't need to actually drive it to charge the 12V battery. If you just turn it on in "Run mode" ready to drive but leave it in Park, it should charge the 12V battery. There's no alternator, the ICE doesn't need to actually be running. The 12V system is powered through an inverter from the traction battery, and that battery gets recharged by the ICE as needed.
ztirffritz wrote:
[quote=Paul F.]
Stop overcomplicating it... replace the battery.
You have a dead battery... It's an EX-battery. It has shuffled off this mortal coil. It's pining for the fjords. It has EXPIRED.
If a good cable-check, cleaning, and tightening, doesn't do it... buy a new battery, install said battery.
That may or may not solve the underlying problem. If he's only driving a short distance/time then a new battery will likely result in the same problem eventually.
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ztirffritz wrote:
[quote=Paul F.]
Stop overcomplicating it... replace the battery.
You have a dead battery... It's an EX-battery. It has shuffled off this mortal coil. It's pining for the fjords. It has EXPIRED.
If a good cable-check, cleaning, and tightening, doesn't do it... buy a new battery, install said battery.
That may or may not solve the underlying problem. If he's only driving a short distance/time then a new battery will likely result in the same problem eventually.
I agree. Use a battery maintainer.
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Speedy wrote:
[quote=ztirffritz]
[quote=Paul F.]
Stop overcomplicating it... replace the battery.
You have a dead battery... It's an EX-battery. It has shuffled off this mortal coil. It's pining for the fjords. It has EXPIRED.
If a good cable-check, cleaning, and tightening, doesn't do it... buy a new battery, install said battery.
That may or may not solve the underlying problem. If he's only driving a short distance/time then a new battery will likely result in the same problem eventually.
I agree. Use a battery maintainer.
If the battery itself is bad, a charger/maintainer isn't going to do anything, because even if fully "charged", the battery may not have enough cranking amps left to actually start the car. I.e. it might be at 12V but only at 10% of its original capacity.
A battery tester will give better insight. This is the one I use: https://www.amazon.com/dp/B01NCS7EF5/ Every battery it has reads as failed has been verified by my local Pep Boys or Auto Zone (I'm usually doing a warranty swap).
Most local auto parts stores will test a battery for free. But you may need to pull it out of the car to have them test it. Heads up if your trunk switch is electronic and not mechanical - I've put one too many batteries back into my wagon by going through the passenger compartment and then awkwardly sitting hunched over in the cargo area trying to maneuver a 50lb battery because I couldn't open the hatch with the battery disconnected (I still think there must be a mechanical release on the inside somewhere but I've never found it).
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OK guys, returning back to this thread...
The voltage I'm reading should be the battery, as I understand it -- I use my Zus and also the procedure described in this YouTube, which gave identical results: https://www.youtube.com/watch?v=9aXrofQmqeQ
(under the Vehicle Signal menu, I didn't use a voltmeter...)
A battery from Amazon is about $170, the solar chargers mentioned in the original post about $70. (I would want to use solar instead of AC since I don't have a garage.)
It is admittedly a 7-year old battery now, and I don't do a lot of driving ... so probably it just sitting around for long periods of time without being driven has maybe done the battery in somewhat? (I'd never had this problem pre-corona.) But as pointed out by some of you above, it shouldn't actually be necessary to drive around to power the battery?
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I would just replace it. I was having odd electrical problems, two different stores tested the battery and said it was fine. Difficulties starting, lights turning on by themselves, weird stuff. I went back in, the guy at autozone literally berated me for buying a new battery, but it immediately fixed all the problems. In fact, it's been a few years. No way it wasn't the battery, so the testing doesn't always work. In my opinion, it's basically the cheapest troubleshooting step you can take.
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kj wrote:
I would just replace it. I was having odd electrical problems, two different stores tested the battery and said it was fine. Difficulties starting, lights turning on by themselves, weird stuff. I went back in, the guy at autozone literally berated me for buying a new battery, but it immediately fixed all the problems. In fact, it's been a few years. No way it wasn't the battery, so the testing doesn't always work. In my opinion, it's basically the cheapest troubleshooting step you can take.
Yep, that's the conclusion I'm starting to come to as well ... just a little nervous about doing the battery swapout myself. It's one thing to watch a YouTube of how to do it, it's another to actually do it. Though it does seem relatively easy, except for accessing some of those recessed nuts.
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A 7 year old battery... replacement cost $170. That's a maintenance cost of $24/year or $2 month.
Replace it.
Even if it ends up not being the battery, you got plenty life out of the old one, and will then have 7-10 years of life in the new one.
I'm not seeing a down-side to going ahead and doing it. I mean, spending $170 always sucks, but, It won't be wasted.
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PeterB wrote: ... just a little nervous about doing the battery swapout myself
Which step makes you nervous?
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mattkime wrote:
[quote=PeterB]... just a little nervous about doing the battery swapout myself
Which step makes you nervous?
The mechanical aspects of getting into the compartment, getting all the stuff loosened up, etc.
This is the YouTube I've been looking at, which does make it clear that you need some specific tools for the task: https://www.youtube.com/watch?v=fpxyXboW4Qo
(also commented on in the original thread)
Oh, and also nervous from the perspective of that some of the Amazon reviews suggest that the batteries can die early for no apparent reason, and that Amazon and the manufacturers will try to pawn off the responsibility onto each other; or if the problem isn't really with the battery but something else, and then replacing the battery doesn't fix it. I'm tempted to call the dealership just to see how much they'd charge for this, but on the other hand I do like to do stuff myself.
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PeterB wrote:
t is admittedly a 7-year old battery now, and I don't do a lot of driving ...
Uh yeah, it's toast. Just replace it. 7 years on a battery is a modern miracle these days...
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