Anyone else having 12V battery issues?

And you always grasp what others write, eh? Did you grasp the distinction between a justified claim of a "design fault" and a circumstance which calls for user adaptation? That was my point and I thought the point of Easy Rider.

PriusChat represents a vocal minority of Toyota customers. Most just drive the cars and seldom sit and listen to the radio of a parked car. If they have a problem, they take the car to Toyota service and it is repaired. The Toyota system works for them. Toyota will respond to us more than others because they watch Prius Chat, but this does not amount to a full fledged cater.

There have been some fine suggestions in this thread. Consider using some or all of them.

 

I grasped it fine. I could see that others were looking at the problem a different way and that's fine. It's an obvious flaw to me, even if someone else sees it differently. No need to repeat myself again. I'd hate to see this forum degenerate into a partisan shouting match as it does elsewhere.

 

And that seemed like a good place to let the discussion die a natural death and I wasn't going to comment further but then.................

It finally sank in that one of my posts was removed because you "reported" it.
If that is true, I think that is hardly the way mature adults handle disagreements when they come up.
But if that's they way you want to play it, others can return the favor.

 

I am afraid I agree with Easy Rider on this one. This subject has been beat to death, and the constant repeating the same chant by GregP507 has become somewhat annoying indeed. Greg... needs to start calling the customer complaint line of Toyota to complain if he expects anything to happen. Repeating the same thing many to many times in one or two forums on here will not accomplish much other than get him a reputation on here, which I wont label because I don't want to be sarcastic.

 

Feel free to report me. I don't think the moderators are the dopes you think they are.

 

SIGH.
No comment.

 

Anyhow.

 

Best idea I've heard yet. Case closed.

 

I've been killing batteries for decades, inadvertantly walking away from cars with the headlights on, and more recently as little as a door ajar, or a damn "map" light.

I think it'll take legislation, but couldn't there be something that would just disconnect the battery whenever the car is off, so it's impossible to drain it.

Probably there is legislation, that you need to be able to use your headlights for illumination, regardless of the car being shut down.

 

Your last sentence is the "rub". There are issues which have no easy solution.

A flat tire, a dead battery, no fuel/charge, all shut you down and require care/planning. They cannot be eliminated, but we all try hard to minimize them. That includes the car makers. How much trying is enough? For some it will always be better than others. When it is hard, we need to try harder.

The great thing is that we have Prius Chat to help each other.

 

Back in the 80's it was happening to me too many times, despite my best efforts to turn off the headlights. That was before warning buzzers were common and about the time when batteries began to no longer tolerate going dead.

I found a cheap 12v electronic buzzer at radio shack, which only passed current in one direction. I connected the leads between the headlight circuit and the ignition circuit. The only time it buzzed was when there was juice in the headlight circuit, and the ignition was off, so that it grounded through any of the circuits connected to the ignition.

It cost about $4, worked great and saved many batteries on mine and friends vehicles.

 

The PIP does have more 12v loads when the car is "off" than the regular gen III. The base version has all the charging circuit logic, the charging timer, detection of plug, plug area LED, etc. The advanced has all this and the charging notification.

This is Prius #4 for me.
2001: 12v battery lasted 9+ years (not sure how long it lasted after I sold it at almost 9 yrs)
(dome lights left on overnight 2 or 3 times...no problem. This model had no smart key)
2004: 12v battery went dead at 8.5 yrs due to leaving the radio on with doors open while washing
2010: still has original 12v battery
2012 PIP: 12v battery went bad after 18 months. Dome light left on once and had to jump start.

A lot of people on this thread have been giving reasons "why" Toyota (and all the other car makers) have chosen to make hybrids (plug in or otherwise) such that the 12v battery and high voltage battery are separated.
I think the only reason it is the way it is is because of cost and the fact that, generally, people are a bit used to the idea that 12v batteries can go dead. There is also a large installed base of services available that can jump start a 12v battery (tow trucks, AAA, another car+cables, 12v battery plus clips, etc.) so they can get by with a system designed 80 years ago, good enough.

But as more and more cars go electric or partial electric, at some point a chief architect is going to get a little bit like Steve Jobs and ask "why the hell should a customer need a jump start when they have a big fully charged battery on board?" I wonder how the Tesla cars work in this regard?

Mike

 

Umm, if you have enough 12v power to turn on the computer and display a message, then there is probably enough power to start the car. There is no starter motor...the 12v is (basically) used to run the computer and closed the relay to the traction battery.

Mike

 

This is true, but when I was experiencing the problems, I wasn't able to turn on the computer by getting into ready mode. In retrospect I've learned that whenever you are able to get the car in ready mode, the aux battery is getting charged. I've learned that if extended periods are necessary, it's best to switch to ready mode instead of acc mode.

The "transparent" solution I was talking about would only occur when there wasn't enough power to get into ready mode.

 

Some interesting reading in this regard here: 12V battery question | Forums | Tesla Motors

 

The simplest solution would be to kill the accessory power when battery voltage drops to a level indicating less than 80% charge. This would be inconvenient, but if the lights could still be turned on (with a warning displayed) it would work well enough. Toyota should also bite the wallet and start supplying the PIP at least with a true deep-cycle battery of more than barely adequate capacity. LiFePO4 batteries are very stable and reliable, and you could fit a higher capacity pack into the same space. It would need a BMS, but if it lasted 6-10 years instead of 2-3, it would help Toyota's image.

The cheapest solution, however, would be to add a third battery: a small UPS type battery that would be kept charged, but not drained unless the accessory battery failed. Then the UPS battery could start the car, with a prominent warning displayed to check/replace the accessory battery immediately.

 

Essentially, that's what I came up with. I keep it under the seat, and I have to attach it to the boosting terminal with alligator clips when I need to give it a boost. It's a lithium ion booster, ( I posted a pic of it earlier in the thread) and had about 75% power in it after being stored for over a year. I could wire in an extra 12V receptacle and leave it plugged all the time if I wanted to keep it topped up. The only drawback to this solution is that the aux battery is damaged each time it goes flat. If I manage to ruin another aux battery in this way, I should replace it with an AGM /deep-cycle battery, as in the Tesla.

There is also a video of a similar wired-in solution, which I posted earlier in this thread also.

 

I've got a used 10AH UPS battery in the back of my Leaf.

 

If only some wise electronics guru could come up with a way to shut the converter off when the traction battery reached a certain voltage. They do it with a $2 part added to protected lithium batteries, and cheap Chinese flashlights, but I guess Toyota can't compete with that advanced technology.

 

It's not rocket science, just common sense. There's plenty of power for a boost; just disable it when the traction battery voltage is too low.

 

I don't claim to be wise electronics guru. Are you? And what if that $2.00 part fails? Is it really reliable? There is quite a bit at stake. You may not trust the care which Toyota engineers take, but I tend to give them the benefit of the doubt. They have a pretty good track record.

If it really does come down to a little more cost to get a lot more convenience, I am all for it.

It is very clear to me that we will not be able to equal what the factory can do in a reliable solution for our cars. What may come in future cars will not change what we have now. Adapt to what you have until a better car is built and you can afford it.

It would make a lot more sense if I was 30 years younger and twice as rich, also.