Gen 3 12V Battery

[Dane]

Hi! In 2 weeks I am taking delivery of a 6 mth 2000k Gen3, I am a bit concerned about the capacity of the 12v Battery. Being disabled, I tend to sit in my car whilst my wife does her shopping, &, depending on where she shops, this can sometimes be 2+ hours.

My question is this. Will I be able to listen to my radio/cds without running the 12v Battery flat so needing a jump start?

Your thoughts please.

[S.J.C.]

Hi! In 2 weeks I am taking delivery of a 6 mth 2000k Gen3, I am a bit concerned about the capacity of the 12v battery. Being disabled, I tend to sit in my car whilst my wife does her shopping, &, depending on where she shops, this can sometimes be 2+ hours.

My question is this. Will I be able to listen to my radio/cds without running the 12v battery flat so needing a jump start?

Your thoughts please.

I don't think you'll have a problem. I go on motorsport events and sit in car all day with a safety radio connected to the Battery and this radio draws a lot more out of the Battery than the normal car one. However I do start the car occassionally and it'll run for a short period and then shut down. If you leave it in the 'ready' mode it'll switch on and off at random intervals to charge up the Battery or run the heating, etc.

Sure you'll enjoy your purchase when yo get it.

[Jan&tone]

Hi! In 2 weeks I am taking delivery of a 6 mth 2000k Gen3, I am a bit concerned about the capacity of the 12v battery. Being disabled, I tend to sit in my car whilst my wife does her shopping, &, depending on where she shops, this can sometimes be 2+ hours.

My question is this. Will I be able to listen to my radio/cds without running the 12v battery flat so needing a jump start?

Your thoughts please.

I've done just that! I don't trust idiots in our local Tesco car park not to scratch my baby, so I sit in it whilst 'er indoors is shopping - rare occasion 'cos she normally takes her Aygo, but never had a problem and once got caught on the M20 for 2 hours when plod closed the road due to an accident, the ready light was on and now and again the engine started to charge the hv Battery. I suspect therefore that the radio/hard drive comes from the hv Battery, not the 12v one.

[timberwolf]

I've done just that! I don't trust idiots in our local Tesco car park not to scratch my baby, so I sit in it whilst 'er indoors is shopping - rare occasion 'cos she normally takes her Aygo, but never had a problem and once got caught on the M20 for 2 hours when plod closed the road due to an accident, the ready light was on and now and again the engine started to charge the hv battery. I suspect therefore that the radio/hard drive comes from the hv battery, not the 12v one.

Your conclusion is wrong.

The source of the 12V supply depends on what mode was selected with the "POWER" switch.

ACCESSORY and ON mode selected with the "POWER" switch (but without pressing the brake pedal) will mean the 12V Battery is powering those 12V accessories such as the Audio system.

READY mode selected with the "POWER" switch whilst pressing the brake pedal will result in the 12V supply coming from the DC-DC Converter at between 13-14 volts via the HV Battery (nominal 201.6 Volts). The 12V supply will not only being supplying all the 12V accessories but also many ECU will be awake, and the 12V Battery will be charging (although possibly not well enough according to some people!?).

As to the original question, it is really difficult to answer that question, whether your 12V Battery will survive in ACCESSORY mode for trips would depend on how much mileage you do, how often you use the car, how often and for how long you sit listening to the Audio system, etc. It's easier just to avoid the problem by using READY mode, yes it in wastes a small amount of petrol, but it isn't much, compared for example with the diesel that the tow truck uses to rescue you

[Dane]

I appreciate your responses folks.

I can see a very steep learning curve in front of me!

[Grumpy Cabbie]

I appreciate your responses folks.

I can see a very steep learning curve in front of me!

It's just a different way of working. In a normal car you will use the Accessory setting to listen to the radio without using petrol but with a risk of running the Battery flat. With the Prius you don't need to use the accessory setting (and risk a flat battery) as leaving the car in the Ready mode will ensure the car looks after itself and will switch the engine on to charge a low Battery etc only when needed. Another benefit is you can also have the heating or a/c on too and (depending on setting) this uses much less petrol than in a normal car.

As a cabbie there are times when I can be sitting for a while between jobs. In a normal car I'd either waste fuel (and money) running the engine or risk a flat Battery as my two way radio, taxi meter, despatch computer and satnav are always running when I'm working and I could also have the radio on too. With the Prius I have no worries as I just leave the car in Ready mode and will usually switch the heating off as doing so means the engine is much less likely to have to switch on and off. The 12v battery is always charged and very little (if any) fuel is used.

Hope this clarifies things a bit more.

[Doesn'tExist]

That's what I would have done, just leave the engine on as it will be off for most of the time So no worries of running it flat.

[Jan&tone]

I've done just that! I don't trust idiots in our local Tesco car park not to scratch my baby, so I sit in it whilst 'er indoors is shopping - rare occasion 'cos she normally takes her Aygo, but never had a problem and once got caught on the M20 for 2 hours when plod closed the road due to an accident, the ready light was on and now and again the engine started to charge the hv battery. I suspect therefore that the radio/hard drive comes from the hv battery, not the 12v one.

Your conclusion is wrong.

The source of the 12V supply depends on what mode was selected with the "POWER" switch.

ACCESSORY and ON mode selected with the "POWER" switch (but without pressing the brake pedal) will mean the 12V Battery is powering those 12V accessories such as the Audio system.

READY mode selected with the "POWER" switch whilst pressing the brake pedal will result in the 12V supply coming from the DC-DC Converter at between 13-14 volts via the HV Battery (nominal 201.6 Volts). The 12V supply will not only being supplying all the 12V accessories but also many ECU will be awake, and the 12V Battery will be charging (although possibly not well enough according to some people!?).

As to the original question, it is really difficult to answer that question, whether your 12V Battery will survive in ACCESSORY mode for trips would depend on how much mileage you do, how often you use the car, how often and for how long you sit listening to the Audio system, etc. It's easier just to avoid the problem by using READY mode, yes it in wastes a small amount of petrol, but it isn't much, compared for example with the diesel that the tow truck uses to rescue you

Thought i might be wrong!

However, Grumpy pretty much confirms what I was getting at. You drive into the car park, put the car in P and sit there. You haven't pushed the Power button so everything is live but the engine is not running.

Leaving the radio/cd/hard drive on the car will look after itself, you can see the HV battery monitor go down slowly and when it gets to two bars the ICE will start up and run for a few minutes putting some charge back into the HV battery. This cycle continues until the wife returns/traffic clears and you cary on as normal

That is why i assumed that when the ready light is lit the power comes from the hv battery and not the tiny 12v one.

[Dane]

Thank you for the advice folks.