Battery Has Discharged!

[Dasbob]

Argghh! Lucky i popped out to the car to get something, i discovered that since yesterday afternoon my Battery has discharged, the car is dead :/

I cant get to the 12v Battery as its in the boot and i cant see how to release the boot. I called the RAC and see what happens when they arrive some time in the next 3 hours.... what i cant understand is how its managed to discharge, i never had the lights on

[cootuk]

Maybe they will link a 12V Battery to the engine Battery point and hope to get enough power just to open the doors.

Or maybe use the manual key to get in, then possibly an override handle on the inside of the tailgate?

[FROSTYBALLS]

Could the interior light have been left on?

[timberwolf]

Interior light or boot light?

Not closing a door or hatch properly? (BTW I like John's Prius User Guide advice to Slam the hatch to be sure).

[Sagitar]

Interior light or boot light?

Not closing a door or hatch properly? (BTW I like John's Prius User Guide advice to Slam the hatch to be sure).

On the Prius, it's easier to use the mechanical switch on the boot light to switch it off permanently so that it will not come on even if you don't close the lid properly. Does the Auris have a similar switch?

This happened to me once. Since then I have bought a low current Battery charger that allows a connection to the 12v Battery from inside the boot. So, open the door with the mechanical key, drop the rear seat squabs to enter the boot and make the connection to the Battery charger.

[Dasbob]

Okay guy came round (sent a local mech) and mentioned that they dont normally touch hybrids (which is fair enough they are not typical cars) any way he still jump started the Battery and car came on straight away with 4 blips on the Battery, that could have been from his charger though.

drove about for 20 minutes never using the electric (thats going to mess my mpg this fuel up :P )

Hopefully it should be fine in the morning, i hope its not something wrong with the car, if it happens again (like tomorrow) i think i will contact Toyota.

I have a theory on why it might have gone. If the starting Battery is what operates the door opening/closing is not connected directly to the hybrid motor.... ie its the 12v battery, and that when using the electric battery the car wont charge up the 12v.... then here is what happened yesterday.

FIrst off i used a 12v socket tyre compressor to pump my tyres up, i then used a 12v vacuum to give car a quick once over.... i then cleaned the car with the keyless entry key in my pocket (which caused the wing mirrors to keep moving back and forth as the car opened and closed). I then drove only 8 miles to fill up the car and abused the hybrid battery along the way as per normal. I came home and left the car for 36 hours.

So my basic guess is that the starter battery is not getting charged up when on electric.... and hence with natural discharge and lots of use of the 12v it caused the problem. .....or i have a dodgy alternator ?

Or it could be what you guys said and the boot light was on... i did take some stuff out the boot to empty it, so that is quite plausible. That sounds a good idea Sag, can you link me what type of charger you brought? I will have to check to see if i can turn the boot light off

Many thanks!

[cootuk]

I thought the hybrids charged the 12V Battery from the HV Battery as long as the car is in Ready, rather than ACC.

There's no conventional alternator, but a DC-DC convertor.

[timberwolf]

Okay guy came round (sent a local mech) and mentioned that they dont normally touch hybrids (which is fair enough they are not typical cars) any way he still jump started the battery and car came on straight away with 4 blips on the battery, that could have been from his charger though.

Your will have two separate batteries, a HV (High Voltage) Battery, and a 12V Battery. If you only have one display, then it would only display the SoC (State of Charge) of the HV Battery. The local mechanic would only have jump started the 12V battery, he would not have attempted to go anywhere near the HV orange cables or battery, and you may have had a dead mechanic to explain to the authorities if he had tried to jump-start the HV battery!

drove about for 20 minutes never using the electric (thats going to mess my mpg this fuel up :P )

Hopefully it should be fine in the morning, i hope its not something wrong with the car, if it happens again (like tomorrow) i think i will contact Toyota.

I think this is unlikely (although it may be difficult to tell) because it takes a long time to fully recharge a flat 12V battery. Did anything reset such as the clock or mpg?

I have a theory on why it might have gone. If the starting battery is what operates the door opening/closing is not connected directly to the hybrid motor.... ie its the 12v battery, and that when using the electric battery the car wont charge up the 12v.... then here is what happened yesterday.

FIrst off i used a 12v socket tyre compressor to pump my tyres up, i then used a 12v vacuum to give car a quick once over.... i then cleaned the car with the keyless entry key in my pocket (which caused the wing mirrors to keep moving back and forth as the car opened and closed). I then drove only 8 miles to fill up the car and abused the hybrid battery along the way as per normal. I came home and left the car for 36 hours.

So my basic guess is that the starter battery is not getting charged up when on electric.... and hence with natural discharge and lots of use of the 12v it caused the problem. .....or i have a dodgy alternator ?

As Cootuk said, the 12V battery will charge as long as the car is in READY mode, it doesn't matter whether the car is being driven on electric, petrol or both, or just sitting in traffic or on the driveway.

Using the accessory modes is generally not recommended for any period of time, including sitting in the car listening to the radio - it is always better to have the car in READY mode with the awareness that the petrol engine is going to periodically start/stop - better to use a small amount of petrol than have a flat 12V battery.

Or it could be what you guys said and the boot light was on... i did take some stuff out the boot to empty it, so that is quite plausible. That sounds a good idea Sag, can you link me what type of charger you brought? I will have to check to see if i can turn the boot light off

Many thanks!

It is never easy to tell whether a 12V battery has gone flat due to accidentally leaving a door slightly open or an interior light left on, OR through slower misuse via the accessory mode (I've always wondered why Toyota included these modes when it can shorten the life of the 12V battery?).

[johalareewi]

Okay guy came round (sent a local mech) and mentioned that they dont normally touch hybrids (which is fair enough they are not typical cars) any way he still jump started the battery and car came on straight away with 4 blips on the battery, that could have been from his charger though.

The 4 blips is for the HV Battery, not the 12v Battery.

drove about for 20 minutes never using the electric (thats going to mess my mpg this fuel up :P )

You don't really get a choice in this. The hybrid will decide when to use petrol and when to use electric. You can 'hint' with EV mode.

Hopefully it should be fine in the morning, i hope its not something wrong with the car, if it happens again (like tomorrow) i think i will contact Toyota.

If the 12V Battery has gone completely flat, it could be faulty. Should be able to get it tested/swapped. Being discharged will have shorten its life so maybe a warranty swap? Plenty of threads on here about 12V battery testing.

I have a theory on why it might have gone. If the starting battery is what operates the door opening/closing is not connected directly to the hybrid motor.... ie its the 12v battery, and that when using the electric battery the car wont charge up the 12v.... then here is what happened yesterday.

The 12V battery operates all the normal electrical stuff like door locks, radio, lights. The HV battery is just for driving the electric motors and for chargin up the 12V battery.

FIrst off i used a 12v socket tyre compressor to pump my tyres up, i then used a 12v vacuum to give car a quick once over.... i then cleaned the car with the keyless entry key in my pocket (which caused the wing mirrors to keep moving back and forth as the car opened and closed). I then drove only 8 miles to fill up the car and abused the hybrid battery along the way as per normal. I came home and left the car for 36 hours.

Always worth putting the car into READY mode when using the 12V accessory sockets for any length of time. Also, you can't abuse the HV battery (even though you think you can). The car's battery management won't let you.

So my basic guess is that the starter battery is not getting charged up when on electric.... and hence with natural discharge and lots of use of the 12v it caused the problem.

The 12V battery is charged up when the car is in READY mode. It is charged from the HV battery.

.....or i have a dodgy alternator ?

Or even no alternator ;)

[Chris Dance]

Using electric tyre pump etc quickly flattens the 12v Battery. I ditched my electric tyre pump and I now use a foot pump.

I experienced a flat Battery on our previous Gen 2 Prius caused by not closing the back hatch properly. I now ensure all interior lights are off. On the Prius you should not jump start the 12v Battery directly, only use the connection in the engine compartment. Is the Auris different to this? I am told that most RAC & AA guys know about hybrids. Good idea is to be in Toyota Club accident & breakdown you get full AA service.

[barrycoll]

interestingly, the car goes berserk with bells and whistles and fireworks, if the door is slightly open, the seat belt not on, etc etc, but does not make a squeak if a life threatening rear view mirror light is left ON...

and another gripe is no lighting for wing mirror open/close button.....always a night time 'grope'

[Peter Sale]

I was struggling with the mirror fold button not illuminated and then realised an easy solution ( I tend to park in daylight and return to the car when dark).

If I fold the mirrors in and then turn off the car, before leaving I press the mirror button again. They don't fold out as the ignition is off but when I get back in the car they fold out without me having to fumble for what appears to be the only non-illuminated button. At least this works in the Auris, you might have to test in the Prius but it has helped me !

[geo13647]

Interesting post. Yours is a new car, comes with free year's AA / Toyota Club membership. I hope they should know about hybrids.

I'm changing my interior lights to LED's & I always leave the cabin interior lights off, as opening the door,or even just walking past the car with your keys, completely ruins your night vision with these 4 searchlights going on automatically.

If yo leave the keys on top of the wipers in a plastic bag (there's no antenna coverage there) you can wash & wax happily, without the car locking & unlocking & the mirrors folding every few mins.

If you have a reasonably handy source of A/C mains, then a good charger/ Battery manager is a CTEK multi XS3600. You can even connect up the supplied cable permanently to the Battery and connect the charger via the connector as required. In fact I know of at least one owner (non hybrid) that has actually installed the complete charger, permanently connected (not the mains of course, the cable's too short :) )in his car. Mine has got me through several winters on various cars.

An electric compressor, as mentioned, is a greedy beggar, & can draw 8 or more amps, this soon flattens the Battery.

Car vac is a thirsty user as well, I'm guessing these would have been the culprits if used on Acc mode (hybrid sys not on).

G...

[barrycoll]

worth a try Peter....thanks for that...

they also flick out if you put them in manually after locking the car.....they go out with a bang after when the car is turned ON

but your way sounds better

[jonesbach]

I suspect you may have my problem.

http://www.toyotaownersclub.com/forums/topic/148440-excel-hybrid-12v-battery-prone-to-discharge/page-2

The trickle charge/discharge regime seems to affect the Battery, progressively reducing its ability to hold charge. After recovering mine, it has not given any further problem, but I suspect it is only a matter of time before it has to be reconditioned again.

I always put the car in ready mode before using the electric tyre pump, though if the Battery was up to scratch it should not matter. A tip if you are going to jump start it yourself, don't manually 'key open' the driver door(to access the bonnet release) until you have everything ready. Opening the door triggers a pump to start and this will totally flatten any remaining charge.

[jonesbach]

I agree the compressor and Vac are greedy beggars, but we are forgetting that this is supposed to be a 35 amp-hour Battery. So, assuming they both use 8 amps, and you pump for 1/2 hour and Vac for 1/2 hour, then you use 8 amp-hours. That should still leave at least half charge even if we started below full charge state.

From other reports on this forum it seems to have become accepted that batteries only last a couple of years and now it is almost unacceptable to expose them to load. As stated in the post I linked to previously, once in the long distant past batteries would last 12 years and still be man enough to turn over an engine. So much for progress!

[Sagitar]

These matters have been discussed before - worth searching for the relevant threads?

When I first had trouble with the 12v Battery, the dealer staff convinced me that my usage of the car, which was admittedly at a low level, was insufficient to keep the 12v Battery properly charged and that a once-in-a-while boost from a Battery charger would be a good thing. That was when I bought the charger (a TecMate Optimate4 - on the recommendation of the dealer service staff). However, the battery gave trouble again subsequently and was eventually (after several attempts) diagnosed as having a faulty cell and was replaced under warranty.

My impression is that that this fault is not wildly unusual in the Prius 12v battery, but I am not sure whether it is inherent or whether occasional accidental full discharges of this relatively small capacity battery cause the fault.

I don't use the battery charger frequently, or as a matter of course, but if the car is little used for a significant period I am inclined to give it a boost. From the length of time that it sometimes takes to achieve a full charge from such a boost, I judge that the battery does not hold full charge in these low-use circumstances.

I do only about six thousand miles a year, the majority of it on short local runs of less than five miles.

[kithmo]

All the interior lights stay on if you leave the hatch open, so it's a bit of a waste of time just turning the boot light off. I turn all the interior lights off if the car is going to be stood for any length of time.

[Dasbob]

Cheers for all this information guys!

I had a think about events a bit more over night and i think its a mixture of over use of the 12, and its suspect ability to charge up well. The clock did not reset or the MPG counter

What i forgot to also mention is when i did take it for an 8 mile jolly to the petrol pump, i had my phone charging, music blaring and the energy screen (which i have always by default had on)... I also dont think it was the boot, as another poster pointed out the car goes crazy if you leave anything open, and when i got the thing back from the dead it didnt beep.

I did have it set so the wing mirrors pop in and out when car is open/shut, so When i noticed the Battery was flat, i did open the car successfully (wing mirrors came out but seemed more groany than normal), i grabbed what i needed from the car, shut the door and locked it... and wing mirrors stayed out for about 1 second, then closed... thats what prompted me to investigate and i opened the car to discover i couldnt start it, the wing mirrors auto groaned to open and that was it...dead

judging from what you guys have said, my guess is the vac + pump knocked me down to 1/2 Battery or less (assuming it was not full any way), then add in the hour i spent cleaning and waxing the car with the mirrors popping out... then i doubt the car did much charging when i drove it as i was using the 12v for my phone. Then when i locked the car and opened it last night you had all the lights and wing mirrors popping out.

Part of me thinks "well what you expect, you are asking a lot more of the 12v than you did in the previous cars" and the other part of me is thinking their might be dodgy cell.

To answer the queries about the mechanic, i have been a full member of RAC for 12 years, so i just rang them up, they told me it would be 3 hours + wait (this was at 9pm)... i got a call back saying they could get a local mech to look at it, so i agreed to that and he showed up 15 minutes later. He said he had jumped them before but "was not suppose to do it" i did point out in the manual it says you can jump it from the front Battery. I understood his hesitation mind, like you said i wouldn't want a hybrid battery discharging into me.

I started today manually doing the mirrors my self when the car is in ready mode, and turned the interior lights off, i cant see how either of them working while the car is switched off can be any good. My dad used to tell me to make sure i always switched my car lights off first before the engine, he worked as a mechanic for 30 years so i like to think he knew something... maybe i should have listened to my parents more :). I think i will invest in a charger and keep an eye on things, the moment it happens again i am going to put on my dissatisfied customer face, but looking at the hassle another poster has gone through, i suspect it be simpler to sort it out myself. Its frustrating as its tainted my view of the car a bit.

Incidentally... i can not recall if i had it in ready mode, maybe power on... but not ready... :( *slap face* so it all could be my own stupidity

[jonesbach]

You do seem to have had some life left in the Battery for the doors to open. When you tried to get in the drivers door a pump would have started.(Some kind of anticipatory action, you can hear it cut in) It takes a fair current as you can hear it labour and then pick up as 'Ready' is reached on start. Once you reach this pump start point you are dead in the water. You can't stop it and it will drain the remaining life from your Battery. It's then jump start with a good Battery or disconnect the 12 volt and put it on charge(You can't charge in situ due to said pump)

You may have drained it by use, but I don't see how it can be by leaving on lights. According to the handbook it will turn itself off and extinguish interior lights if they are left on. I've seen this myself re. boot light. If you leave the boot open the light will go out itself after 10-20 minutes and will not come on again until you shut then reopen the boot.

[MLW2233]

There are a few key questions here.

Gen 2 or 3?

How old is the Battery?

The key is these 'normal' Toyota 12volt batteries seem very fragile. The first heavy drain, or age (i.e. over 4 years old) and they seem to have no capacity at all, and die. The dash lights go funny, central locking goes funny. alarm goes wacky etc etc.

Solution is... take out the Battery and give it a slow long small charge for 12+ hours.

Then start again. Anymore trouble (give it one chance) and go straight to Europarts and buy a Bosch silver 4 year guarantee Battery (about £52+), and all will be well for 4 years.

Can't understand why Toyota made this simple 12 volt battery the source of so much trouble, when for no money, a simple beefy Ford Focus type battery would solve most of the issues.

Also for £64 Toyota's AA cover is unbeatable......the lot......including Europe.

[johalareewi]

Gen 2 or 3?

How old is the battery?

I think the OP has a brand new Auris Excel.

[timberwolf]

Can't understand why Toyota made this simple 12 volt battery the source of so much trouble, when for no money, a simple beefy Ford Focus type battery would solve most of the issues.

It would increase the capacity only. I think the fundamental problems would remain.

The key problem with Lead acid batteries is that for them to work well and to have a long working life they need to be kept fully charged most of the time.

In the days before lots of electronics in cars, the Battery had one main purpose, and that was to crank the engine. Cranking the engine caused a heavy, short term, drain on the Battery, and once the engine was running, a large alternator would quickly recharge the Battery.

In modern cars, when the car is "asleep", there are a number of drains on the 12V battery, the increasingly fancy remote unlocking receivers, car alarm, but there are also IMHO really dumb convenience designs, such as automatically switching off head-lights after the car is off, or worse still timed head-lights to light your way to your front door!, self-folding door mirrors, unknown pumps and fans that hum and whirr when the car is off, and on the Toyota Hybrid another heavy little usage being the brake pump.

The problem is that these standby uses of energy are not replaced immediately because they drain battery power when the car engine is off, therefore the 12V battery remains under-charged (i.e. not fully charged) for longer periods.

On Toyota's Hybrids, the problem is further compounded because a number of owners suspect that the charging via the DC-DC converter is not sufficient, so the 12V battery is never fully recharged for many owners, more so for cars that are not driven daily and short journeys.

Lead acid batteries are not a reliable or well suited match for modern cars.

[johalareewi]

Although Toyota hybrids do have a leisure type Battery which is better suited to periods of drain between charges but it is pretty feeble compared to what you would have in a caravan. On the other hand, beefier Battery = more weight.

[jonesbach]

Timberwolf,

In general I agree with your post, but with regard to the DC to DC converter I don't think it is so much underpowered as tending to switch to trickle charge too soon. I certainly agree that the Battery is almost never anywhere near full charge.

The reason I can't agree it's underpowered is that I've monitored voltage when driving(using meter) and when it does produce 14.4V charge this is not pulled down by lights, AC, radio etc. If it did not have the capacity you would expect to see a dip.

It may be switching to trickle charge due to the Battery developing a surface charge, or another possibility is its location in the boot. While it does have a reasonably heavy cable connecting to the front, it does not appear to use a separate 'voltage detecting' cable that is not load carrying. This means that while charging current is flowing, the DC to DC converter, computer, or whatever controls charging up front will be seeing a higher voltage than that actually at the Battery and will therefore tend to cut back early.