Prius 3 Traction Battery

[inspiredron]

As can be seen from my separate post today I have had problems with the 12V Battery on my Prius 3 at just 2 years old.

A very long time ago I noticed that the traction Battery indicator NEVER goes to FULL but always stops one bar below full. I mentioned this to the garage and they responded that "they never do on the Series 3". Although the Series 2's indicator seems to fill completely I accepted this as a "feature" rather than a "fault". With my recent 12V problem and the feeling that the garage fobbed me off when I first reported that issue I am not so sure.

I have never seen the indicator go below 2 bars, as the ICE then cuts in.

Can you please complete the poll so that we can assess whether the not filling is intentional. I guess that this is more important for those of us who only have the 5 year Battery warranty

Thanks

[kithmo]

Normally the HSD Battery indicator only goes up to the last but one bar, but if you drive down a long hill, regenerating energy will fill the Battery indicator, then the car will dump the energy by running the engine.

The HSD Battery itself never gets fully charged or fully discharged, IIRC full battery indicator = 80% battery charge and empty battery indicator = 40% battery charge.

Your poll doesn't allow for the fact that some people regularly drive down long hills and some (like me) don't.

I've only seen my HSD battery indicator full once when I drove down a long incline in the Yorkshire dales, normally it's between one below the top and two bars at the bottom.

[Flaninacupboard]

If i park up with 7 bars then in the morning when i head down the hill i get 8 bars. Also if i sit in stop and go traffic a while i will get to 8 bars (because when driving the plugin system is powering the car, and then when braking the regen goes into the battery). Never seen below 2 bars, even when i am sure it -should- have gone down to 1.

The poll is a bit misleading, there are only 8 bars, no-one can have 9.

Grumpy is correct about 8 bars = 80% and 1 bar = 40%.

[inspiredron]

then the car will dump the energy by running the engine.

Do you mean "by running the electric motor"?

And sorry about the wrong number of bars - Poll now corrected to 6, 7, 8 bars. When I wrote the post mine was down to 5 and I misjudged the maximum which I can now see is 8. I have never seen more than 7 or less than 2.

[Flaninacupboard]

then the car will dump the energy by running the engine.

Do you mean "by running the electric motor"?

Both. It burns petrol to turn the engine and uses electricity to push against the engine. This allows it to dump unwanted electricity. This will only happen if you go down a mountain. Usually, if you get to a high SOC the car will just favour electricity heavily while driving until you get back to 6 bars.

[Grumpy Cabbie]

No, by running the engine. The engine is spun to get rid of the extra power that would otherwise be going into the full HV Battery. The engine does not use fuel whilst being spun like this but can rev rather high sometimes. If you're heading down a long steep hill you might want to try 'B' option on your gearshift as this helps stop too much charge go in (in lay mans terms).

For what it's worth my HV Battery indicator has been sitting at 5 bars a lot lately, though will pop back to the normal 6 when I get going on a run. Wonder if it's a failing 12volt or maybe a failing HV? I'm out of warranty now and the dealers did check everything a week ago and said all is ok.

I'm getting the impression over my last two years that the gen3 Prius just isn't quite as hardy as the gen2appears to be. Hmmm time will tell.

[Opifex]

No, by running the engine. The engine is spun to get rid of the extra power that would otherwise be going into the full HV battery. The engine does not use fuel whilst being spun like this but can rev rather high sometimes. If you're heading down a long steep hill you might want to try 'B' option on your gearshift as this helps stop too much charge go in (in lay mans terms).

Agree with your explanation GC.

Putting it a slightly different way, as you drive up a hill the car gains potential energy. When you go down the hill the energy has to go somewhere and in a normal car it is converted to heat in the brakes. In the Prius the potential energy is first converted to electrical energy to recharge the Battery but there is a limit to how much energy the Battery can hold. When this is reached, rather than use the brakes, the engine is turned without fuel and the resulting compression of the air causes heating, hence converting the energy (that can no longer go into the battery) into heat. The effect is the same as using low gear when going downhill in a normal car.

[johalareewi]

I'm out of warranty now

Haven't you got another year to go?

or have you done all your miles?

[johalareewi]

FWIW.

Normal operation of my gen3 is min 2 bars, max 7 bars but as others have said, you can get it to 8 bars by going down a long steep hill.

[Grumpy Cabbie]

I'm out of warranty now

Haven't you got another year to go?

or have you done all your miles?

3 years OR 60,000 miles. I'm now just over the mileage. Guess there's still a little protection in that I still get the car serviced by the main dealers. I know from past experience that if something occurs just out of warranty and you have remained loyal to the Toyota dealer network, then they will often assist you - depending on the issue. Sometime's they'll replace it all and sometimes they ask for you to pay just the part or the labour.

[r04drunner1]

FWIW.

Normal operation of my gen3 is min 2 bars, max 7 bars but as others have said, you can get it to 8 bars by going down a long steep hill.

Same for me. Mostly a max of 7. I've only ever seen 8 bars a couple of times, but it does happen. Goes back down to 7 again very quickly around this neighbourhood...