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Filliam H. Muffman wrote:
[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: https://www.wildetoyota.com/how-to-jump-...pstarting/ ... 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? 
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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PeterB wrote:
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)
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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Gareth wrote:
[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: https://www.youtube.com/watch?v=fpxyXboW4Qo
(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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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.
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.
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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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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Gotta say, as a Prius owner here I didn't know this about the alternator, as was also mentioned above:
https://en.wikibooks.org/wiki/Automobile...yota/Prius
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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mikebw wrote:
Gotta say, as a Prius owner here I didn't know this about the alternator, as was also mentioned above:
https://en.wikibooks.org/wiki/Automobile...yota/Prius
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.
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Well, maybe my boneheaded move wasn't so boneheaded after all.
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wurm wrote:
Well, maybe my boneheaded move wasn't so boneheaded after all.
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).
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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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