What I learnt from charging my Prius

He's right about item 0.

The batteries are not interconnected, and there's no way they could be. The batteries running the drive system are 280V at very high current. Every bulb in the car would probably explode at that voltage, and so would the 12V battery if exposed to this voltage. Hopefully, this person won't go running out to his Prius to try to conect one system to the other. If he does, I hope his insurance is paid up...

AAMOF, there is an exact procedure for disconnecting the drive-line batteries from the system, and has to be done in the proper order or the batteries will explode, the person will be fried, the driveline ruined or all three.

Reply to
Hachiroku
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Not on any Prius I ever saw. Once the 12V is dead, the car will not run.

There may be, but if the 12V dies, you can't turn the car on.

Reply to
Hachiroku
  1. Some people in the newsgroups write things they don't have a clue about.
  2. The Prius batteries are somehow interconnected. When I forgot to switch off the light, *both* were discharged.
  3. It is hard to charge the battery. When you connect your Prius to another car's battery, the system thinks that there is enough voltage in the batteries, so it doesn't charge them. When you break the connection,
  4. All, or almost all, automobiles are poorly designed. They should switch off the light when the battery is close to be discharged. Imagine a computer which, if you forgot to close the windows before switching it off, requires a maintenance.
  5. This has nothing to do with charging, but another problem with all cars is, if you raise the parking brake during movement (in case of Prius, stomp on the parking brake), it is a guaranteed accident. Imagine a calculator which explodes into your face each time you try to divide by zero! A reasonable car would display the word "ERROR". No, I never raised the parking brake, but the thought that if I did, I could die or kill somebody else, is uncomfortable.
  6. Manual for Prius is poorly written.

I am now going to sell my Prius and never buy any car until car manufacturers start to make cars at least as intelligent as a pocket calculator.

Reply to
urod

From page 366 of the 2010 Prius manual:

"To prevent 12 volt battery discharge

If the interior lights and personal lights [are] on when the door is not full closed or[and?] the interior light switch [is] in [the] door position, the lights will go off automatically after 20 minutes."

I can't make sense out of this as written. Bracketed entries are mine, otherwise quote is verbatim.

Looks like the 2010 has the feature you want but only if you have the light switch in the door position. In other words, if you manually switch the lights on (not in door position) and leave them on, the battery will be drained.

The manual goes on to say the time lapse can be changed by your dealer. You are referred to page 587 where a long list of customizable features begins and runs through page 592.

Reply to
Al Falfa

Unfortunately, it is not possible to customize the intelligence of every buyer.

Reply to
News

Remove your bracketed "and?", and it makes sense.

  1. If the interior lights and personal lights are on when the door is not fully closed, they will go off automatically after 20 minutes.

  1. If the interior light switch is in the door position and the door is not fully closed, the interior light will go off after 20 minutes.

Reply to
Michelle Steiner

So true. The battery in my 2005 was fully discharged twice, once when my sig-o left the overhead light on after digging in her purse and once when I left the hatch door ajar. The first time we just jumped the 2005 to her car, started it, and let it charge the battery itself. The second time I simply put my charger on the handy little post in the fuse box for a couple of hours. It just doesn't seem to be all that hard, but then I have jumper cables and a charger, both being necessities where I live.

Reply to
Al Falfa

The ONLY way they're connected is that the car needs the 12v battery to turn on the car, which means engaging the drive system (and its integrated electrical component). If the 12v battery goes dead, the relays that turn on the drive system don't open. The drive system is isolated and drains no energy, either from its gasoline component or its electrical storage component.

Charge up your 12v battery, or put in a new one, and it will turn the car on and close the relays that engage the electrical component of the drive system. No problem.

Now: should you leave the car turned ON, and you leave lights on, and then it runs out of gas, you will exhaust the entire drive system, and it will turn off. Then the 12v battery takes over, and then IT exhausts, and you have nothing left in the system whatsoever.

This is just like any other car. Any GM would do the same thing.

It would pay for you to examine just how your car works before making incorrect assumptions and statements.

Not at all. You put a battery charger to it. You DO mean the 12v battery that the user interfaces with, right? Because that's the ONLY battery you interface with, the ONLY battery you would be charging.

Again, read up on your car if you're interested. You'll find that the traction battery (which the user never interfaces with) is charged when the car is delivered to the dealer. Should the dealer service dept have to replace a traction battery (let's say there's been an accident), there's a unique machine that travels to that dealership to support charging the traction battery after a new one has been installed.

It's not as simple as "turn the car on and let it do its thing".

The 12v battery, you mean. I agree. My Honda has a system that turns off interior lights after 5 minutes of leaving the door open. You have to pay for the top trim level to get that, though--and if you use the pushbuttons to turn on the interior lights, it leaves them on regardless. When you have kids playing around in a van, that's going to happen. Sucks. It's not rocket science to fix that--but neither Honda nor Toyota has bothered.

ummmmm....yeah? So? If you stick a knife in your eye, you'll hurt yourself. I can go on and on stating the blindingly obvious. Why is this a problem in your universe?

you know, if you're going down the highway at highway speeds and you cut the wheel 180 degrees, you're going to have an accident and involve other people on the road as well. Why is any of this a problem for you?

If you're uncomfortable with the fact that PHYSICS WORKS, maybe you should sit home in a plastic bubble.

Sure, it could be better. On the other hand, a reasonably intelligent person--say, someone who actually has $25K to spend on a car--won't have any problems getting through it.

And everyone benefits.

Reply to
Elmo P. Shagnasty

So far so good.

Yup. Just like my Honda. Stupid, ain't it.

With other cars that use standard size 12v batteries, you can buy batteries that shut themselves down before they're all the way out.

Reply to
Elmo P. Shagnasty

And yet, they're allowed to vote and drive on the same roads I drive on.

Reply to
Elmo P. Shagnasty

Having done this in my 2010, I know for certain that:

If the interior light is on (the one above the console) and the door is closed, that light will stay on indefinitely. Fortunately I caught mine in this state after only an hour and the battery in my 2010 still had enough juice to power-up the starting system.

Reply to
Al Falfa

And drink, and text, and....

Reply to
News

Leave Noddy alone.....

Reply to
Al Falfa

yourself. I can go on and on stating the blindingly obvious. Why is this a problem in your universe?

No, eyes are hard. It is physically hard to cut them off, and the pain would cause you to stop it long before you do any harm (until you really want to blind yourself and determined to do it). Human body is robust.

No, after starting rotating the steering wheel, you would hear two dozen klaxons which would force you to stop. But pushing one pedal instead of another seems an easy to do mistake, and takes only fraction of second.

Reply to
urod

That I understand, but I suspect there is a step-down DC to DC converter hidden somewhere in the car, so that the big battery could charge the small one.

Reply to
urod

There is a DC-DC converter built in to the inverter unit under the hood. It is current limited and fused at 100 amps on the 12V side.

Reply to
Daniel who wants to know
  1. > If the interior lights and personal lights [are] on when the door is not

full closed or the interior light switch [is] in [the] door position, the lights will go off automatically after 20 minutes."

switch in the door position. In other words, if you manually switch the lights on (not in door position) and leave them on, the battery will be drained.

Nope. The interior light switch has 3 positions "off", "door", and "on". I left it in the "on" position. As far as I understand this text, only the "door" position is protected.

  1. >> It's hard to charge a battery

battery that the user interfaces with, right? Because that's the ONLY battery you interface with, the ONLY battery you would be charging

Here is what I did.

(1) I bought a car battery charger (namely, Hella power-charger) and put it to the 12V battery. Nothing happened. I waited for 30 minutes. Nothing happened still. Maybe the charger was defective.

(2) With two cables, I connected the 12V battery to the 12V battery of another car. I hit the Power button, my car turned on. The power meter showed half-full 200V battery (5 blue lines). The system did not switch on the engine. I waited for 1 minute.

(3) I disconnected the 12V battery. My car turned off. I hit the Power button. Nothing. Not surprising at all, considering that the system hadn't switch on the engine at the previous step, so it couldn't charge the 12V battery.

(4) I connected the batteries again and turned the joystick to the "R" (Reverse) position. The road was tilted downwards, so the system switched on the engine, which started to charge the battery. Only this way I was able to charge it.

(5) After disconnection the batteries, the power meter showed almost empty 200V battery (1 red line). I cannot explain the behaviour of the power meter, unless two batteries are interconnected (via DC-DC converter)

Reply to
urod

No, they are not directly interconnected. But...if they were, the larger battery has enough juice (6.5 Ah at 201VDC or roughly 15x the little battery) to run your little 12VDC overhead light for several DAYS.

You can charge the little 12VDC battery with a conventional battery charger but...why would you want to? Once you jump the little battery, the 12V system will power up the computers, close the main power relay to the big battery, and start the gasoline engine (if necessary) to charge everything up. At that point you should disconnect the jumper cable and close the hood.

Most of the 12v lights on the Prius (and most newer cars) switch off automatically after a fixed period of time if left on with the vehicle not running. Some do not on the assumption that the owner wants the lights on for some reason. The one I have heard of on the Prius that sometimes causes problems is the little light in the cargo compartment in the back.

It's not just a 'parking' brake but also an 'emergency' brake and no, it is not a guaranteed accident if you stomp on it. It is a completely separate mechanical braking system designed and intended to be used if the main hydraulic braking system is non-operational (usually because of a loss of hydraulic pressure due to damaged brake lines or lack of maintenance.) It is a 'guaranteed accident' if you your main braking system fails and you do not use the emergency braking system. I suggest that you take your vehicle to a wide-open area with no other vehicles around and then practice using the emergency braking system so that you become familiar with how it operates in an emergency.

I don't want the car to show 'error' when I push the emergency brake...I want it to slow down and stop.

The manual for my 2006 Prius is reasonably well written...no better or worse than manuals I have for vehicles from GM, Honda, and Chrysler. My complaint about car manuals in general would be that they don't put enough technical information in them.

Perhaps try a bicycle? Bonne chance!

Reply to
David T. Johnson

You are confused! The Volt, unlike the Prius hybrid, is a true electric vehicle. The only thing its engine does is drive the generator. The Volt could be left "on" indefinitely, there is no flow of current until you active the motor.

Reply to
Mike Hunter

New switched mode chargers will not turn on unless they sense some minimum voltage of the correct polarity on the leads. If the 12v is discharged to 0 volts the charger won't turn on. In this case you need an old "dumb" charger to bring the voltage up so that the "smart" charger will start charging.

You probaly didn't push the brake pedal far enough and the car was in IG-ON mode instead of READY mode.

12V charge has nothing to do with the engine running as the car does not have a 12v starter or alternator.

You must have managed to hit READY instead of IG-ON this time.

The DC-DC is only active any time the READY symbol is lit up so 12V charge is only dependant on READY it has nothing to do with anything else. READY is also a sign that the system main relays on the HV battery are closed and allowing power to the inverter.

NIMH state of charge cannot be determined by voltage alone so the battery ECU has to guess what the SoC is any time 12v power is lost. You could probably disconnect and reconnect the 12v battery 5 times and get a different HV SoC reading each time. FWIW 1 pink/red bar is actually 40% SoC and all green bars is actually 80-82% SoC. This 40-80% window is the main part of why the battery lasts as long as it does.

Reply to
Daniel who wants to know

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