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12V Battery dead on 2017 XSE

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#21 ·
marcuslaw said:
You are risking both damaging a relatively complex hybrid engine system and, in going against Toyota's recommendation, potentially being denied warranty coverage.
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So, I shouldn't jump any vehicles? Or should I jump vehicles ONLY with the access point under the hood, as the manual states?
 
#22 ·
Edwin617 said:
So, I shouldn't jump any vehicles? Or should I jump vehicles ONLY with the access point under the hood, as the manual states?
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What part of the quote from the manual do you not understand?

To prevent damaging the vehicle
The exclusive jump starting terminal is to be used when charging the 12-volt
battery from another vehicle in an emergency. It cannot be used to jump
start another vehicle.
Click to expand...
 
#23 ·
Here's an update. After jumping 3 vehicles this winter by connecting jumper cables directly to my 12v battery in my trunk and jump starting the other vehicles. This is the voltage on my 12v battery today. It is being displayed on my inverter, and then again on my multimeter.
 

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#25 ·
LOL. Why are we trying to save this guy folks? Let Darwin.......I mean Edwin have his way. Clearly it is 100% safe to boost with the rav4 12 volt battery and there is no chance of damage what-so-ever. He has proven Toyota engineers and common sense wrong. You just can't argue with that level of intelligence.
 
#26 ·
Nodnerb said:
LOL. Why are we trying to save this guy folks? Let Darwin.......I mean Edwin have his way. Clearly it is 100% safe to boost with the rav4 12 volt battery and there is no chance of damage what-so-ever. He has proven Toyota engineers and common sense wrong. You just can't argue with that level of intelligence.
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There's clearly a possibility of damaging anything when you do anything. That isn't my argument. I'm just saying that 1 jump will LIKELY NOT damage his battery. That's just stupidity. I don't have to jump vehicles with my RAV anymore, since I got myself a jump pack. However, people were telling me that it will damage my vehicle, and it hasn't. So CLEARLY, I am not wrong in saying what I've said.

You can go elsewhere with your corny insults.
 
#27 ·
I have a degree in electronics and I completely disagree. If you jump a car with a really dead battery, in really cold weather, from a tiny battery like we have, what do you think happens? All that current draw is taking your battery down FAST, likely seconds of cranking. Under those circumstances it is very possible to blow your inverter, converter or any of the running computer systems when you try draw 100+ amps off that little battery. It could dip well below the voltage thresh-hold to keep your car "running". But yes, if you boost an only slightly low battery just on the edge of starting it *probably* would maybe possibly be ok. But as you stated on the previous page that you've *proven* it is ok to jump start with the hybrid,.........you certainly are wrong. It is never safe, or ok, you just got very lucky
 
#29 ·
Nodnerb said:
I have a degree in electronics and I completely disagree. If you jump a car with a really dead battery, in really cold weather, from a tiny battery like we have, what do you think happens? All that current draw is taking your battery down FAST, likely seconds of cranking. Under those circumstances it is very possible to blow your inverter, converter or any of the running computer systems when you try draw 100+ amps off that little battery. It could dip well below the voltage thresh-hold to keep your car "running". But yes, if you boost an only slightly low battery just on the edge of starting it *probably* would maybe possibly be ok. But as you stated on the previous page that you've *proven* it is ok to jump start with the hybrid,.........you certainly are wrong. It is never safe, or ok, you just got very lucky
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Get a refund for your degree. I got lucky 3 times? Fine. Thanks for your input.
 
#30 ·
:egad: Looks to me it's nearly time to close this thread.
 
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#33 ·
Nodnerb said:
I have a degree in electronics
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What kind of electronics? :wink



Nodnerb said:
Under those circumstances it is very possible to blow your inverter, converter or any of the running computer systems when you try draw 100+ amps off that little battery.
Click to expand...

The inverter in the hybrid system is the pinnacle of modern electrical engineering, at least as far as high efficiency DC-DC switching converters go. It is designed with safety in mind and longevity under extreme operating conditions.


Do you honestly think there is no over-current protection like it is some $1 Chinese gadget that burns out if you put in the AA batteries backwards? :surprise
 
#34 ·
BobVila said:
What kind of electronics? :wink






The inverter in the hybrid system is the pinnacle of modern electrical engineering, at least as far as high efficiency DC-DC switching converters go. It is designed with safety in mind and longevity under extreme operating conditions.


Do you honestly think there is no over-current protection like it is some $1 Chinese gadget that burns out if you put in the AA batteries backwards? :surprise
Click to expand...

I've always respected your posts as it relates to electronics. Let me ask you this. Do you really think it's safe to boost a dead car in the cold winter, posssibly drawing 100+ amps off a battery and system primarily designed to only power a few micro controllers? Do you see a lot of motorcycles boosting cars? The main purpose of the 12 volt battery is to run the computers until the traction battery starts the car. The tiny battery reflects that. If you think no damage can possibly happen to the battery, or the sensitive computer systems when drawing that much current off that battery that powers them, then by all means, boost away. I happen to agree with Toyota to not boost with the hybrid 12 volt battery.
It all depends on how "dead"the boosted battery is. If boosted battery only needs 10 amps from yours......probably ok. If boosted battery needs 90 amps off your battery, you will have problems. It's in the math....but also common sense to anyone who I would assume has a basic understanding of electronics.
If you don't understand that, or need clarification, I've lost respect for your electronics knowledge.
 
#35 ·
Nodnerb said:
Do you really think it's safe to boost a dead car in the cold winter, posssibly drawing 100+ amps off a battery and system primarily designed to only power a few micro controllers? Do you see a lot of motorcycles boosting cars?
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Motorcycles don't boost cars because it won't work in 99.9% of cases. It is safe in the sense that the worst that can happen is a fuse on the cable that runs front to back will blow.


Nodnerb said:
If you think no damage can possibly happen to the battery, or the sensitive computer systems when drawing that much current off that battery that powers them, then by all means, boost away.
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You can't damage a small lead acid battery by "overloading" it. You can damage it by putting a wrench across the terminals and leaving it there. But trying to jump a large load from a small battery will not damage it.


The small battery will basically see a short across the terminals and deliver all the amps it can. For the hybrid lead acid battery that's around 120-150A cold cranking amps. About 200 if it's a warm day.



That's exactly how large batteries work under extreme conditions. If you need to start a really cold engine your battery will provide as many amps as it can. And if it's too cold, it just won't turn over. The battery won't be damaged. It provided all the amps it could for a few short bursts. That's what car lead acid batteries are designed to do.
 
#36 ·
I agree that the battery is the least likely to be damaged per se. But the hybrid systems, computers, and charging systems currently running off of the battery and converter could very well be affected during that sudden high amp draw.

I guess we have to agree to disagree. There are lots of reports of damage from boosting with a hybrid car. Also reports of no damage for others, as in this thread. As I said before I believe it has a lot to do with the state of the battery being boosted. I won't chance it with my car. Especially since it would void any warranty because Toyota also advises against it.
 
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