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Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 12:28PM
[forums.macresource.com]

... seems like the battery is maybe having trouble holding a charge? I can jump it, but after jumping it and driving around a short time, then letting it sit for about a week, it needs a jump again. What's weird is that once it's jumped, it's showing a charge of 14.2 - 14.7V ... which would seem to be good. (I've measured this using both my Zus and also the Prius' internal diagnostics screen.)

So... question is whether I'd be better off buying a new battery and installing myself, or perhaps getting one of those solar trickle chargers mentioned in the thread.




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)
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Re: Followup to Prius battery woes
Posted by: ztirffritz
Date: February 10, 2021 12:34PM
I assume you're talking about the lead acid 12v battery?

You need to run your car for a while for it to recharge. There's probably a bit of phantom drain from various electronics in the vehicle. Some vehicles keep the 12v accessory ports powered even if the vehicle is off, so you might want to check if you have anything plugged in there. I'd probably just get a good battery charger to maintain it if you have a way to plug it in.

I recommend something like this:
[www.amazon.com]



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Re: Followup to Prius battery woes
Posted by: Schpark
Date: February 10, 2021 12:38PM
Also the 14.2-14.7V is the alternator not the battery.
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Re: Followup to Prius battery woes
Posted by: space-time
Date: February 10, 2021 12:39PM
Just move your hamsters in the car.
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Re: Followup to Prius battery woes
Posted by: ztirffritz
Date: February 10, 2021 12:42PM
Quote
space-time
Just move your hamsters in the car.

smiley-laughing001goodoneagree smiley



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Re: Followup to Prius battery woes
Posted by: btfc
Date: February 10, 2021 12:55PM
Jumping and driving for a short time is usually not adequate to fully recharge a dead battery. Put it on a charger. The way the charger acts will tell you a lot about what shape the battery is in. Also, clean/tighten battery clamps and ground points.
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Re: Followup to Prius battery woes
Posted by: Microman
Date: February 10, 2021 01:14PM
I replaced my Daughters trunk battery , 2014 Prius. Its the same size as a normal battery, but costs more. I think I went dealer, and 10% off or something...
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Re: Followup to Prius battery woes
Posted by: macphanatic
Date: February 10, 2021 01:19PM
Using a voltmeter is not the best way to test a battery. There are testers meant for just this purpose. They create a load on the battery. Autozone or similar should have them.





As suggested, check the cables to make sure that they're clean and tight.
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Re: Followup to Prius battery woes
Posted by: Paul F.
Date: February 10, 2021 01:38PM
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.



Paul F.
-----
A sword never kills anybody; it is a tool in the killer's hand. - Lucius Annaeus Seneca c. 5 BC - 65 AD
----
Good is the enemy of Excellent. Talent is not necessary for Excellence.
Persistence is necessary for Excellence. And Persistence is a Decision.

--

--

--
Eureka, CA
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Re: Followup to Prius battery woes
Posted by: ztirffritz
Date: February 10, 2021 02:08PM
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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Re: Followup to Prius battery woes
Posted by: GGD
Date: February 10, 2021 02:27PM
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.

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.
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Re: Followup to Prius battery woes
Posted by: Speedy
Date: February 10, 2021 02:38PM
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.



Saint Cloud, Minnesota, where the weather is wonderful even when it isn't.



Edited 1 time(s). Last edit at 02/10/2021 02:38PM by Speedy.
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Re: Followup to Prius battery woes
Posted by: Gareth
Date: February 10, 2021 03:44PM
Quote
Speedy
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: [www.amazon.com] 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).



Edited 1 time(s). Last edit at 02/10/2021 03:44PM by Gareth.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 04:19PM
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: [www.youtube.com]
(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?




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)
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Re: Followup to Prius battery woes
Posted by: kj
Date: February 10, 2021 04:21PM
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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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 04:25PM
Quote
kj
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.




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)
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Re: Followup to Prius battery woes
Posted by: Paul F.
Date: February 10, 2021 04:29PM
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.



Paul F.
-----
A sword never kills anybody; it is a tool in the killer's hand. - Lucius Annaeus Seneca c. 5 BC - 65 AD
----
Good is the enemy of Excellent. Talent is not necessary for Excellence.
Persistence is necessary for Excellence. And Persistence is a Decision.

--

--

--
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Re: Followup to Prius battery woes
Posted by: mattkime
Date: February 10, 2021 04:35PM
Quote
PeterB
... just a little nervous about doing the battery swapout myself

Which step makes you nervous?



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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 05:18PM
Quote
mattkime
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: [www.youtube.com]
(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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Re: Followup to Prius battery woes
Posted by: fauch
Date: February 10, 2021 05:31PM
Quote
PeterB
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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Re: Followup to Prius battery woes
Posted by: mikebw
Date: February 10, 2021 05:32PM
Quote
PeterB
Quote
mattkime
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: [www.youtube.com]
(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.

Given the age of your battery it's not gonna hurt to just replace it, no matter if that is the problem or not. It's time.

Call Advance Auto or whatever your local parts shop is to get a price. Then call the dealer to get the installed price. Judge if it's worth your time to install yourself.

Wrenching out batteries is not a big deal, they are made to be replaced without headaches.
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Re: Followup to Prius battery woes
Posted by: GGD
Date: February 10, 2021 05:34PM
Quote
Gareth
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.

In a Prius, the 12V battery is more like a PRAM battery, it doesn't do any "cranking", it just keeps the electronics alive to startup the systems to get the traction battery system engaged. The main thing that normally drains the 12V battery when the car is "off", is the keyless access system. I think it also keeps another rechargeable battery charged that is used for the brake system.

From my experience with a 2007 Prius, the need for jump starting became more frequent when the battery was about 6 years old, and stopped occurring when I replaced the battery.
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Re: Followup to Prius battery woes
Posted by: mattkime
Date: February 10, 2021 05:49PM
do you have a batteries plus near you? They might install. No reason to go to a dealership for something like this.



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Re: Followup to Prius battery woes
Posted by: space-time
Date: February 10, 2021 05:51PM
Quote
space-time
Just move your hamsters in the car.

I'd like to issue a public apology, some people here found my commend very rude.
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Re: Followup to Prius battery woes
Posted by: macphanatic
Date: February 10, 2021 06:02PM
Quote
PeterB
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: [www.youtube.com]
(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?

Are you using a battery tester or a volt meter. If the later, this doesn't give a true indication of whether or not the battery is good. A battery tester puts a load on the battery while measuring the voltage. Big difference in the readings.
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Re: Followup to Prius battery woes
Posted by: Filliam H. Muffman
Date: February 10, 2021 08:18PM
Are the battery terminals and cable clamps free of oxide? It looks like $170 is a very good price for an AGM battery for a 2014 Prius III.

I am not sure about a Prius, but it typically takes 20 minutes to fully charge a 12 V battery with the gas engine running continuously at over 1500 rpm. Just idling at 800 rpm won't do it.

Did you use a Prius forum to get a recommendation on the solar charger?



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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 08:34PM
Quote
Filliam H. Muffman
Are the battery terminals and cable clamps free of oxide? It looks like $170 is a very good price for an AGM battery for a 2014 Prius III.

I am not sure about a Prius, but it typically takes 20 minutes to fully charge a 12 V battery with the gas engine running continuously at over 1500 rpm. Just idling at 800 rpm won't do it.

Did you use a Prius forum to get a recommendation on the solar charger?

Thanks everybody for information. The solar charger recommendation was from the original thread -- don't recall who made the suggestion, but I thought it seemed like a reasonable idea.

The voltage check -- as I said, done through Zus, but the Prius diagnostic screen is through the car itself, and I would assume the diagnostic is really measuring the voltage as load is put on it ... at least, one would hope so for a self-contained diagnostic!

I am tempted to try what Filliam has suggested, before I replace the battery. I was curious, so I Googled and found this: [www.wildetoyota.com] ... which says to let it run for 8 hours (!!!) in Ready mode after jumpstarting ... I suppose I can do that, I have nothing to lose ... could just leave the car running overnight or something. Gas isn't really a problem for me at the moment. (Under non-corona conditions, I typically buy about $20-30 worth of gas, usually about 20 gallons, which lasts me 4-6 months.)

And yes, it may be time for a new battery. I know the manufacturing quality isn't what it used to be -- car batteries lasting 10+ years being a distant memory.




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Edited 1 time(s). Last edit at 02/10/2021 08:35PM by PeterB.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 08:34PM
Quote
space-time
Quote
space-time
Just move your hamsters in the car.

I'd like to issue a public apology, some people here found my commend very rude.

Greatly appreciated, thanks.




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Re: Followup to Prius battery woes
Posted by: Filliam H. Muffman
Date: February 10, 2021 08:46PM
Quote
PeterB
I am tempted to try what Filliam has suggested, before I replace the battery. I was curious, so I Googled and found this: [www.wildetoyota.com] ... which says to let it run for 8 hours (!!!) in Ready mode after jumpstarting ... I suppose I can do that, I have nothing to lose ... could just leave the car running overnight or something.

Wilde Toyota does mention that their procedure is intended to take into account Milwaukee Winter temperatures. Has it been snowing recently in NO? smiling smiley



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Re: Followup to Prius battery woes
Posted by: C(-)ris
Date: February 10, 2021 09:02PM
AAA if you are a member will do it for $218 installed at your house.



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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 09:18PM
Quote
Filliam H. Muffman
Quote
PeterB
I am tempted to try what Filliam has suggested, before I replace the battery. I was curious, so I Googled and found this: [www.wildetoyota.com] ... which says to let it run for 8 hours (!!!) in Ready mode after jumpstarting ... I suppose I can do that, I have nothing to lose ... could just leave the car running overnight or something.

Wilde Toyota does mention that their procedure is intended to take into account Milwaukee Winter temperatures. Has it been snowing recently in NO? smiling smiley

No, but the heat/humidity down here wreaks havoc on batteries of all kinds -- I've never seen so many corroded AA and AAA batteries in my life, since being here. You can't leave batteries in remote controls, etc., without discovering that they've eventually corroded and leaked. Maybe it's been less of an issue here lately, because like many other parts of the country, it's been unseasonably cold.

And the $218 from AAA, that includes the battery...? That would be quite a deal!




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Re: Followup to Prius battery woes
Posted by: Gareth
Date: February 10, 2021 09:33PM
Quote
PeterB
This is the YouTube I've been looking at, which does make it clear that you need some specific tools for the task: [www.youtube.com]
(also commented on in the original thread)

To reiterate from the original thread, while you need specific tools, they are common tools you'd find in any "mechanic's" tool set, or any socket set with metric sockets, and you could spend less than $20. All you need is a 10mm deep socket and a 1/4" ratchet. (Don't bother with the torque wrench).

But if any local auto parts store sells the appropriate battery, one of them will probably install it for free also.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 10, 2021 09:45PM
Quote
Gareth
Quote
PeterB
This is the YouTube I've been looking at, which does make it clear that you need some specific tools for the task: [www.youtube.com]
(also commented on in the original thread)

To reiterate from the original thread, while you need specific tools, they are common tools you'd find in any "mechanic's" tool set, or any socket set with metric sockets, and you could spend less than $20. All you need is a 10mm deep socket and a 1/4" ratchet. (Don't bother with the torque wrench).

But if any local auto parts store sells the appropriate battery, one of them will probably install it for free also.

Yep, I got that ... and I may very well already have all the right tools, with the possible exception of the metric stuff -- I'll have to check. So I AM really tempted to try this myself! (Remember, the issue is that I'm strictly self-isolating, and really avoiding contact with people as much as possible... so going to the local auto parts store is really out of the question...)




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Re: Followup to Prius battery woes
Posted by: AllGold
Date: February 10, 2021 11:41PM
Get a quote from the dealer. The Prius 12V batteries are expensive but in my case the surprisingly small markup from the dealer was worth it to not have to mess with the install. The dealer always wanted a ridiculous amount of money for things like air filters or wiper blades, but the 12V battery was a good deal.

After the battery is replaced and until things get back to somewhat normal, you will probably want to drive the car a minimum of once a week. You could get that solar battery maintainer but it won't help the main traction battery which might also degrade if the car is never driven.

Quote
kj
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.

I had a couple weird problems like that myself when my 12V battery was low. The 12V battery powers the car's computers so if the computers are getting insufficient voltage things can get um, interesting.



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Re: Followup to Prius battery woes
Posted by: RAMd®d
Date: February 11, 2021 05:37AM
Some great points were mentioned in the thread.

Sure, it's a good idea to load test the battery and charging system.

But I go with the battery being bad, given its age, the lack of driving, and the typical ambient temperature.

One key point is driving the car for 20min on the freeway, at freeway speeds.

This keeps the RPM up consistently, unlike in stop and go traffic.

As pointed out, at ~1500RPM, the alternator is charging at ~14.5V, and will bring any typical car/truck battery to full charge.

But depending on its condition, the battery may not hold a charge due to lack of capacity as it ages.

Get a new battery, and get a battery maintainer like a Battery Tender Jr or similar.

A maintainer, unlike a trickle charger that may not perform a maintenance charge, can charge then maintain that charge indefinitely, without having to monitor or disconnect it.

Or, it could be connected once or twice a month for a time as dictated by the LED indicators, then disconnected and stored.

But any way you cut it, seven years is a really good run, particularly for getting only casual care.

Time to get a new one.





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Re: Followup to Prius battery woes
Posted by: mikebw
Date: February 11, 2021 09:01AM
Gotta say, as a Prius owner here I didn't know this about the alternator, as was also mentioned above:

[en.wikibooks.org]
Quote

Recharging the 12 volt battery
Unlike normal cars, the Prius does not charge the 12 volt battery via an alternator spun by the engine. This vehicle charges its 12 volt battery from the hybrid system, so if you are unable to take the car out for a run for any reason, just switching the system on for a while will do the job. To maintain charge in the 12V battery if the car is not being used often, Toyota recommend putting the car in 'Ready' mode for one hour, once per week. If the battery is completely flat, the vehicle may need to be put in 'Ready' for 4 - 8 hours to fully recharge. Be aware that the engine will start occasionally to ensure the high voltage battery doesn't discharge - so this should only be done in a well-ventilated area, not a closed garage. Doing this will also wreck your miles per gallon record. Alternatively, the 12 volt battery can also be recharged using a standard car battery charger.

Good to know that it can recharge the 12v by itself, but for times when you cannot wait it still seems prudent to keep a small jump 12v starter pack in the car.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 11, 2021 10:32AM
Quote
mikebw
Gotta say, as a Prius owner here I didn't know this about the alternator, as was also mentioned above:

[en.wikibooks.org]
Quote

Recharging the 12 volt battery
Unlike normal cars, the Prius does not charge the 12 volt battery via an alternator spun by the engine. This vehicle charges its 12 volt battery from the hybrid system, so if you are unable to take the car out for a run for any reason, just switching the system on for a while will do the job. To maintain charge in the 12V battery if the car is not being used often, Toyota recommend putting the car in 'Ready' mode for one hour, once per week. If the battery is completely flat, the vehicle may need to be put in 'Ready' for 4 - 8 hours to fully recharge. Be aware that the engine will start occasionally to ensure the high voltage battery doesn't discharge - so this should only be done in a well-ventilated area, not a closed garage. Doing this will also wreck your miles per gallon record. Alternatively, the 12 volt battery can also be recharged using a standard car battery charger.

Good to know that it can recharge the 12v by itself, but for times when you cannot wait it still seems prudent to keep a small jump 12v starter pack in the car.

Wow!! VERY good info here -- that part I've bolded is definitely not what I've been doing, so will give it a try. (Money is kind of tight for me right now, and if I can get away with not having to change the battery for a bit -- especially considering that I'm not doing that much driving right now -- all the better.)

Edit: so this basically means doing the same thing that the other video posted says to do -- essentially starting the car up and letting it idle for 6-8 hours. I could easily do that during the course of the day, just leave it parked and running ... since obviously I don't want to be sitting in the car that whole time, I presume I should start it up, then lock the doors and let it run. I don't really care if it uses up gas, since I have plenty stored away.




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)



Edited 1 time(s). Last edit at 02/11/2021 10:38AM by PeterB.
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Re: Followup to Prius battery woes
Posted by: wurm
Date: February 11, 2021 10:49AM
Well, maybe my boneheaded move wasn't so boneheaded after all. smiling smiley
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 11, 2021 11:46AM
Quote
wurm
Well, maybe my boneheaded move wasn't so boneheaded after all. smiling smiley

Nope, not at all ... in fact I have done something similar to this, when I was grocery shopping and wanted to make sure that the groceries were all kept cold as I was unloading them into my house (pre-corona, of course). By keeping the car running for an extended period, the AC kept the inside ice-cold and allowed me to take my time getting stuff right into the freezer/refrigerator (this is an issue down here where the heat is such that, otherwise, your stuff could all be melted by the time you get it inside).




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)
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Re: Followup to Prius battery woes
Posted by: GGD
Date: February 11, 2021 12:53PM
Maybe a good way to proceed is the following.

Give the 12V battery a good charging by letting the car "Run" while parked.

At the same time, start go through the initial steps in the battery swap process which is mostly removing panels to get access to the battery but stop short of disconnecting the battery.

This will give you an idea of the process, what tools you might be missing, and how comfortable you are in doing it yourself.

Then, after a good charging, if you find that the car still needs jumping as frequently, you'll have a better idea if you should just order a new battery to change yourself, or find a place to do the complete job.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 11, 2021 01:11PM
Quote
GGD
Maybe a good way to proceed is the following.

Give the 12V battery a good charging by letting the car "Run" while parked.

At the same time, start go through the initial steps in the battery swap process which is mostly removing panels to get access to the battery but stop short of disconnecting the battery.

This will give you an idea of the process, what tools you might be missing, and how comfortable you are in doing it yourself.

Then, after a good charging, if you find that the car still needs jumping as frequently, you'll have a better idea if you should just order a new battery to change yourself, or find a place to do the complete job.

Good ideas, all around.

Also ... should I be concerned of the possibility of theft, if the car is left running unattended like this...?




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)
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Re: Followup to Prius battery woes
Posted by: Acer
Date: February 11, 2021 01:26PM
As I said in a previous thread, you can change this battery while wearing a tuxedo. It is that easy. And yeah, forget the torque wrench, good heavens, who does that on a battery outside of the factory?
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Re: Followup to Prius battery woes
Posted by: Filliam H. Muffman
Date: February 11, 2021 01:59PM
Quote
Filliam H. Muffman
Has it been snowing recently in NO? smiling smiley

Wow, spoke too soon. Weather Channel said there is going to be snow in the northern parts of LA on Monday. smiley-shocked003

I wasn't sure how the Prius charged the 12 V battery, good to know it is charged slowly off the drive battery.



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Re: Followup to Prius battery woes
Posted by: mikebw
Date: February 11, 2021 05:59PM
Quote
PeterB
Quote
GGD
Maybe a good way to proceed is the following.

Give the 12V battery a good charging by letting the car "Run" while parked.

At the same time, start go through the initial steps in the battery swap process which is mostly removing panels to get access to the battery but stop short of disconnecting the battery.

This will give you an idea of the process, what tools you might be missing, and how comfortable you are in doing it yourself.

Then, after a good charging, if you find that the car still needs jumping as frequently, you'll have a better idea if you should just order a new battery to change yourself, or find a place to do the complete job.

Good ideas, all around.

Also ... should I be concerned of the possibility of theft, if the car is left running unattended like this...?

I assume you have the wireless key thing, so you can start the car by pressing start. Exit the car and then see if you can lock it with you and the key being on the outside. It might not like it, but if that works you should be OK. The car will run without the key until it gets turned off, so don't just leave it ON with the doors unlocked, if you think someone might steal it.
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Re: Followup to Prius battery woes
Posted by: PeterB
Date: February 11, 2021 06:56PM
Quote
mikebw
Quote
PeterB
Quote
GGD
Maybe a good way to proceed is the following.

Give the 12V battery a good charging by letting the car "Run" while parked.

At the same time, start go through the initial steps in the battery swap process which is mostly removing panels to get access to the battery but stop short of disconnecting the battery.

This will give you an idea of the process, what tools you might be missing, and how comfortable you are in doing it yourself.

Then, after a good charging, if you find that the car still needs jumping as frequently, you'll have a better idea if you should just order a new battery to change yourself, or find a place to do the complete job.

Good ideas, all around.

Also ... should I be concerned of the possibility of theft, if the car is left running unattended like this...?

I assume you have the wireless key thing, so you can start the car by pressing start. Exit the car and then see if you can lock it with you and the key being on the outside. It might not like it, but if that works you should be OK. The car will run without the key until it gets turned off, so don't just leave it ON with the doors unlocked, if you think someone might steal it.

Right, but if someone somehow gets in the car with it running, can't they just drive off with it? (They wouldn't be able to start it up again without the FOB, but they might not care about that...)

Edit: my FOB doesn't start the car, I have to press the On button to do that, but I can exit the car and then just lock it manually with the manual key.




Freya says, 'Hello from NOLA, baby!' (Laissez bon temps rouler!)



Edited 1 time(s). Last edit at 02/11/2021 06:57PM by PeterB.
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Re: Followup to Prius battery woes
Posted by: GGD
Date: February 11, 2021 09:04PM
I was thinking that you'd practice the battery swap at the same time as you're letting the 12V recharge with the car "On", so locking wouldn't be an issue.

But if you do lock it while running with the key outside the car, for the most part nobody will even know that the car is "On". The ICE will shut off when the traction battery is sufficiently charged, and the 12V will be recharged off of that silently. That may eventually drain the traction battery to the point where the ICE needs to recharge it again, but those periods should be relatively short and for the most part the car should be silent and look like any other parked car.
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