Best Way To Drive A Hybrid

[timberwolf]

Yes, when it is in Ready mode.

I think the not having to drive X miles was because in a conventional car you needed to have the engine RPM up above idle so that the alternator was generating more electricity to recharge the Battery. Probably isn't necessary with modern alternators?

[Cyker]

Most cars will charge the Battery when idling, but it will take forever so it's better to go for a run to get the RPM up so it charges faster :)

As you say, the HSD doesn't need to since it doesn't have a standalone alternator and can charge the 12v directly via the HV :)

I'm guessing in Duffryn's case the AA guy just powered up the car and left it in Ready mode while he was talking - I imagine the low capacity of the HSD 12v means it can be charged to a safe level relatively quickly.

Say, does anyone know if the HSD 12v is a deep-cycle Battery or just a smaller standard car Battery?

[johalareewi]

Say, does anyone know if the HSD 12v is a deep-cycle battery or just a smaller standard car battery?

Deep cycle.

[Cyker]

Ah, again the sensible choice!

It's really weird that so many people are having this problem then

I wonder what the amp draw on the HSD's 12v system is?

Deep-cycle batteries, esp. Gel ones, can usually be left quite a long time... I do know they really hate being put under high load (If you tried to start a car with one, you'd probably kill it! ) but they can be discharged to nearly nothing and recharged back up to 100% lots of times without degrading too quickly.

Most car batteries OTOH will be pretty much dead if you discharge them below 25-50% more than 5-6 times!

[timberwolf]

I have my doubts about them being deep-cycle as both my original Toyota 12V and the replacement seem as bad as any regular lead-acid 12V car Battery. When you take them out the acid sloshes around so they ain't gel as far as i can tell. On the mains charger they charge up on the regular setting, and monitoring them with a volt meter has never demonstrated that they have longer lifespan. The Bosch S4 I bought as temporary replacement seemed just as good except I didnt want to file down the vent hose elbow adapter.

I think the deep-cycle/gel/leisure is a myth and Toyota are selling a regular 12V Battery with their own vent hole size.

[johalareewi]

I think the deep-cycle/gel/leisure is a myth and Toyota are selling a regular 12V battery with their own vent hole size.

You could be right.

I should have said it ought to be a deep cycle Battery.

Looking on Prius Chat, it would seem that the Gen3 does have a type of deep cycle 12V Battery.

http://priuschat.com/threads/12v-battery-voltage-management.110449/

[Cyker]

Well.. if that's the case, it may be worth seeing if you can get a deep-cycle Battery to fit in there as it might mitigate the problem a bit (Again, assuming the amp draw isn't too high!)

Unless it's a proprietary form factor, there's a good chance there is a deep-cycle one that'd fit and have the right lugs, but might be a bit pricey.

The batteries themselves are hard to tell apart externally as the chemistry and construction is pretty much the same; Both can be gel, flooded or glass-mat type, and can have similar packaging.

The only real difference is that deep-cycle batteries have fewer plates than starter batteries but they are much thicker plates to resist degradation, whereas starters have loads of very thin plates for maximum surface area, which is why they have waaay higher amp draw and also why discharging them too low kills them very quickly (The thin lead plates get munched!).

[Cyker]

<Dupe Dupe Delete Me!>

[Lustral]

Wow didnt expect to come back to this thread with so many replies.

Anyways , i havent driven my fathers Auris for about a week now (been on holiday , driving my Yaris etc etc) , will prolly drive it again on Saturday. Im hoping it will start up fine , even after non usage for about 9 days ...

Ill give it a good run this weekend

[Lustral]

I have noticed on my drive back home today there seems to be condensation on the corner of the headlight casing on the inside ... Is this normal or shall I take it back to Toyota for inspection ?

[Cyker]

A little is okay I think, my Yaris gets that now and then.

Just keep an eye on it to make sure it doesn't start looking like a fancy fishtank!

That said, given how new it is I'd not expect condensation so quick?

[PeteB]

Wow, what a broad discussion.

I've driven over ¼million miles in Hybrids since 2002, mostly Prius, but a little in Hondas and Lexus, along with a day and half day respectively in the Auris and Yaris Hybrids. I'm still learning things even now, but have picked up quite a lot over time. I currently drive a 2012 T3 Prius with cruise control added.

12V battery:

the original Mk1 Prius really suffered with the low capacity of the Battery, because 1) the issue wasn't initially understood and 2) once flattened a few times they were even more dodgy. Later Hybrids have slightly higher capacity 12V batteries and the drain when everything (except alarm, door lock sensors etc.) is off has been reduced.

I think the main reason for the small Battery was part of the original Prius design rationale to reduce every possible inefficiency, so weight, tyre rolling resistance and drag were just as important as the Hybrid system. Indeed, it might not look slippery, but the 4 door saloon "Classic" Prius (aka Mk1) had an astonishing .32 CD (drag factor). However, a pristine 12V Battery in a Classic with fault free electrics would be lucky to survive 3 weeks in an airport car park, Because the original Prius was not a quick seller (and was not intended to be), many had flat batteries by the time they came off the ship, and were flattened many more times in the dealers' showrooms or car lots, reducing life even further.

Parking lights could flatten them in just 4-5 hours, less if the battery was in decline. My first Classic needed a new 12V battery at 2 years and about 25,000 miles - to my surprise, replaced under warranty without hesitation. My second Classic still had it's second battery after 9 years and 160,000 miles!

The Prius (and other Toyota/Lexus Hybrids) certainly need much less power to fire up since the HV battery takes charge of starting the combustion engine, and a number of users have reported being able to get it going with something like a power tool battery!

HV (high voltage) Battery:

as others have said, it's very hard to flatten this, as the software works hard to protect the different parts of the Hybrid system (one reason you can't turn off the traction control). I've only heard of two instances, both due to the car being fuelled with diesel! The driver, then AA/RAC, then dealer made so many attempts to start the system it went below the threshold of being able to start the engine. At that time there was only one charger in the whole of Europe, and it took up to a month to book it to be delivered to the dealers concerned, by which time in both cases the battery had died. I imagine if the engine had some other fault, repeated starting could have the same dire consequence.

The only other thing that might kill the HV battery is extended use of 'N' (neutral) whilst in Ready mode (assuming this hasn't changed on the Gen 3 - I've not tested it since Mk1 & 2). If the petrol engine is running when you select N, it will stay running until you switch off, select P, R or D, or you run out of petrol! If the engine in not running when N is selected, it stays off. After a while a warning message appears on the MFD, but I have no idea if a safety cut out would operate before the HV battery became dangerously low. I did discover in a Classic that dropping the HV quite low prevents Reverse from working until the engine has restored some charge.

Accessory Mode (i.e. all the warning lights are off, but not "Ready", audio system, SatNav and other main screen functions work):

I think this is useful if you want to sit for a short while listening to the radio or program the SatNav, but since the windows aren't active (even though the folding mirrors are!) it's of limited use. I too use Ready mode if sitting in the car for any length of time, but this does have a price - in addition to any fuel used charging while parked, the system works harder to build the HV battery level back up over the next mile or two. Doing it a lot can knock 1-2 mpg off the tank to tank value (BTW - the calculated MPG is usually 2½-3 mpg optimistic when I calculate the value after a 500-530 mile tank-full).

Drive Modes:

The Mk2 (2004-2009) Prius introduced the EV button; PWR and ECO appeared on the Gen 3 (2009 on).

• EV mode prevents the petrol engine from starting unless:
  • the warm-up process has started
  • the HV battery is too low (usually 3/4 bars or less)
  • HV battery is too hot
  • you accelerate too hard
  • You exceed 30 mph (20 when cold in some models - 60 in the plug-in Prius)
  • the heater is demanding a lot of heat (or front screen defrost mode is on)
  • the system doesn't feel like it for some other reason!
• Normal mode: (all other modes off) linear response to the accelerator
  
• ECO mode: first half of accelerator pedal travel gives reduced acceleration (max power still available when floored), also aircon is degraded to aid economy (also very useful in snow/ice for avoiding wheel spin)
  
• PWR mode: power comes in quickly early on - beware, overuse can cause rapid front tyre wear - I heard of one driver who used it all the time, until he needed new front tyres after 10,000 miles!

There will always be some disagreement on the most economical method of driving, and much depends on other factors, but I've found using ECO mode all the time, and trying to limit acceleration so that the ECO meter goes no higher than the middle of the right half of the main ECO gauge area works best, although in heavy traffic that goes out of the window if there's other cars behind! My Classics and Gen 2s got better results from flooring it until desired speed reached (subject to traffic!), then being gentle.

Also on Gen 3, best regen is achieved by getting the ECO gauge to just reach the far left of the "charge" area - brake much harder and you're burning brake parts instead.

Tyres:

One last thing - on the Gen 2 Prius Toyota spent millions getting the drag coefficient to an incredible .26, and then to .25 on the Gen 3 (that doesn't sound a lot, but the scale is non-linear, just like the earthquake scale) BUT only on the T3 with it's 15" wheels (which is why I chose one). I could have gone for a T4 or T-Spirit with 17" wheels which give the following 'advantages':

• harsher ride
• more road noise
• drag goes back up to .27 - worse than the Gen2!
• worse mpg and CO2
• bigger turning circle
• harder to fit wheel under boot floor after a puncture
• more expensive tyres when replacements needed

Regards, PeteB

[Ningpo]

Interesting to learn all about the different problems with the 12v Battery, have to agree with all the positive comments made.

As regards the braking system, under normal driving conditions the pads and discs hardly get used as the car is slowed down by the electric motor going into reverse when you hit the pedal, the discs and pads come into use to finally bring you to a halt.

With low vehicle usage this can result in the discs becoming rusty but an easy way to get rid of this is to drive the car up to about 30mph( on a clear, quiet road)slip the car into neutral and brake hard.

Because the car is not in drive, the braking system alone will be utilised and if done occasionally will keep the discs and pads up to scratch. This was all related to me by a Toyota technician but have yet to try it for myself so any info on this would be welcome.

On my gen.3 Prius there is not even a hint of a ridge on any of the four discs after 15000 miles in 3 years and the brakes are as sharp as ever and only 10% pad wear evident on its first MOT recently.

Hope all this is of interest.

[timberwolf]

If you replace "going into reverse" with "becomes a generator" then I would agree with you. The way you have written it could also mean that the direction that the motor is spinning changes direction, and that would be incorrect.

To get into Neutral, you need to hold the gear shifter for about 2 seconds, and I don't think there is any need to brake hard, because when you are in Neutral all the braking will be friction braking. As for how often, I only do it if the brakes make a grinding noise when I first drive off. Also I am little cynical about the braking hard advice, it is either a hang over from when they didn't mention Neutral gear, or it is just a way to get the customer to wear out their brake pads quicker? :)

[valmiki]

I may be wrong but if you are in Neutral and you brake, both front and rear pads are used to slow down, that's why it is suggested, otherwise the rear pads never get cleaned off? is that right?

[PeteB]

I may be wrong but if you are in Neutral and you brake, both front and rear pads are used to slow down, that's why it is suggested, otherwise the rear pads never get cleaned off? is that right?

Yes, spot on.

I agree with timberwolf it's not necessary to bake hard.

I'm told that even when braking gently and the regenerative braking is operating, the friction brakes are applied very gently to make sure they're clean, warm and dry if you suddenly need to brake hard enough to bring in the 'real' brakes.

Also, if a wheel loses grip during braking, going over a wet manhole cover, for example, if the ABS kicks in regen braking stops and the car reverts to real brakes until the pedal is released and reapplied.

Rgeards, PeteB

[Lustral]

Great looks like my fathers hybrid has died. The car hasn't been driven for 1 week and it is not responding to unlock via the keyfob or unlocking via the key. What would have caused this issue ?

My faith in hybrids have taken a dive now.

I'll ring the AA a bit later to sort it out after I have done some errands.

Just wondered if any owners have any answers

Thanks

[Lustral]

Finally got into the car using the key stock , however the car is dead. Just called Toyota roadside assistance and they will be over in a hour.

Had a look under a bonnet and I can't see where I can jump start it

[Lustral]

Great ... they sent a Ravenscroft person who couldn't do anything with hybrids at all and told me to speak to the dealer on Monday ... Lucky the car is at home or i would have been spitting bullets.

The Ravenscroft man said never ever jump start a hybrid as there is too much voltage in the Battery and can damage the Battery and/or car.

I think i will stick with my petrol Yaris for now ...

[PeteB]

Great ... they sent a Ravenscroft person who couldn't do anything with hybrids at all and told me to speak to the dealer on Monday ... Lucky the car is at home or i would have been spitting bullets.

The Ravenscroft man said never ever jump start a hybrid as there is too much voltage in the battery and can damage the battery and/or car.

I think i will stick with my petrol Yaris for now ...

Hi sorry I didn't see this earlier in time to be of some help.

I would expect it to be like the Gen 2/3 Prius, where the jump start terminals are under the bonnet, under a plastic cover next to the fuse box. Best to find the manual if you can and look for the picture.

It's easy to flatten the 12v Battery on a Toyota Hybrid because they use smaller, lower capacity batteries because they don't have to start the car, just the computers and breakers that activate the High Voltage Battery. Of course, that means there's less contingency for parking lights, using the radio in Accessory Mode, leaving a door/boot slightly open etc. However, with everything off you and a well charged 12v Battery in good condition there should be no problem parking up for 3-4 weeks.

There's a big discussion called "Battery Has Discharged!" if you want chapter and verse.

In short, it's rubbish that a jump start can harm the Hybrid (as LONG as you get the leads the right way round). That said, some people claim to have got one going with a drill battery and some bits of wire.

Once it's going, just driving (or leaving in "Ready") for half and hour should rejuvenate it, even when the petrol engine's not running, as in Ready Mode the HV battery provides power to the 12v side all the time.

The original Gen 1 Prius was most prone to this problem and many of us carried a jump starter in the boot, but after being caught out once I never needed mine again.

Good luck, regards, PeteB

[Joseph D]

Great ... they sent a Ravenscroft person who couldn't do anything with hybrids at all and told me to speak to the dealer on Monday ... Lucky the car is at home or i would have been spitting bullets.

The Ravenscroft man said never ever jump start a hybrid as there is too much voltage in the battery and can damage the battery and/or car.

I think i will stick with my petrol Yaris for now …

I'd also be onto AA roadside assist and giving them a blast about sending an incompetent agent. Jump starting a hybrid is not rocket science, with the correct knowledge.

[wass]

Jump starting a gen 2 is really easy. Its the 12 volt Battery which will be flat and not the high voltage Battery. Almost any 12 v Battery will do.... even from a small motorbike since all you have to jump start is the computer... the starter motor is driven from the high voltage battery not the 12 volt battery which will be the one which is flat. Why does the battery go flat? Well with a conventional car you hear the poor old battery starting to give up the struggle. With a hybrid, you just don't hear the 12volt battery in action because it isn't responsible for turning over the engine and so the batteries give in with little or no notice.

[vorlon69]

Why am I not getting 72.4mpg?

I try to drive this the proper way (I think) for hybrids - gentle acceleration, gentle braking etc but only 50mpg sucks!

[Surv1v0r]

Why am I not getting 72.4mpg?

A recent study by The International Council on Clean Transportation (ICCT) showed that, on average, ‘real world’ fuel consumption for new cars was 21% worse than the figure quoted by the vehicle manufacturer (AA Link).

According to "This is Money", the Prius is claimed to get 70.6mpg but actually only gets 52.2mpg (LINK). According to What Car? "Buying a Toyota Prius may be a perfect choice for some people who drive around town a lot, but not for others who may spend a lot of time on motorways.'"

As Mark Twain said, "There are three kinds of lies: lies, damned lies, and statistics.". To this should certainly be added ANY figure quoted in ANY manufacturer's brochure ;)

FUELLY seems to have some realistic mpg figures, Honest John and SpritMonitor.de may also help to give more accurate figures? As I have posted elsewhere, vehicle manufacturers could almost certainly access VERY accurate mpg figures from the ECU each time a car is serviced by a main dealer. Publishing an average of these figures would probably yield a more honest (but less flattering) result.

[Grumpy Cabbie]

It's all how you drive it. The hybrid isn't magic. Hammer it and you'll get rubbish mpg's. The Euro test is a 'best you're ever likely to get' mpg figure, though if you try really really hard you can better it.

I'd get 65-75 mpg on my 25 mile commute to York on the flat. That would drop to 55 mpg in winter when the engine runs longer to heat the cabin. Certainly not the 52 mpg quoted by WhatCar, but my new 5 mile commute is much harder on the car in that it barely warms up before I'm at work. I'm now getting 45 mpg. Still not bad in the conditions.

So the conclusion is that the mpg's depend on your circumstances and driving style. You'll probably get more in a hybrid as your engine is more likely to be off in traffic compared to a traditional car. A lot of diesels have stop/start which is ok at traffic lights, but more traffic is a slow start stop crawl of 0-5 mph where the hyrbid engine is off. Horses for courses.