Excel Hybrid 12V Battery Prone To Discharge

[jonesbach]

I took delivery of my hybrid in January and initially had no problems. However, a month ago the 12V Battery went totally flat when not used for 2 days. I monitored the Battery voltage for a few days, but even with a 40mile journey it failed to recover, averaged 12.3-12.5V, and it had to be used daily to achieve that. The charging circuit looks OK as it is providing 14.5V. I took it to the dealer who ( over the period of 36hrs. that they had the car) were unable to reproduce the problem and suggested I recharge the Battery. Not very helpful!

Since getting the car back I've tried to isolate the issue, and discovered that the high(er) drain on the battery seems to result from the Smart Entry when

(1) it is near a Wifi transmitter(overcame that by moving the car),

(2) in the rain when the door handles are wet over a long period.

I don't believe there is a fault in this circuit, but that it is applying extra load on the battery and either the 12V system is not up to requirements or the 12V battery is faulty. The first seems unlikely, but the dealer claims the battery is OK(although he has not tested it when disconnected from the vehicle)

Has anyone experienced a similar problem or can anyone suggest anything else that would discharge the battery(I have shut off all interior lights)

[Peter Sale]

That doesn't sound good at all and not fit for purpose. I often don't use mine for a few days or go a long journey and wouldn't be happy if it suffered like that.

Other than trying another dealer (some are better than others and more determined) there may be a couple of things left to check although I am sure you have.

Do the sun visors have lights for the mirrors ?. I have known that cause problems.

On the Honest John forum I have seen, but not necessarily agreed with, the comment that you should turn the radio off at the on/off switch rather than doing this via the ignition. Seems strange to me but then you have to cover everything.

I previously had a 1.8 Yaris SR with smart entry and know that the key used to go through a fair amount of batteries but there was never an issue with the car. Had my Auris for two months now and had not better tempt fate.

My suspicion is that your Battery has a faulty cell which the dealer is failing to diagnose. My Gen 2 Prius suffered from this but that was due to age. Voltage would show healthy at first and then drop as you watched it - down to about 9V. Fortunately I got it changed before it let me down.

Best of luck, will be interested to hear how you get on.

[Aceshigh84]

It does say in the handbook about getting the door handles wet (i.e. when washing) as it activates the central locking and folding mirrors - could it be that when you were noticing the Battery drain, if it had been raining all night for example, your car would have been constantly unlocking (& then auto locking again after 30 seconds) thus draining the Battery.

It is possible to disable the smart entry - at least to troubleshoot, but I suppose that now summer is finally here you may not notice it any more?

[jonesbach]

Thanks Peter, Acehigh84,

I'll double check the interior lights and the thought of changing my dealer, even if it means a 30 mile journey, has occurred to me.

Re. door locks. It's possible I forgot to lock on the occasion I had the complete discharge, though I have been in the habit of checking that the door mirrors have folded. I am waiting for the rain to return(I can't believe I said that) so that I can make a final check and then give it to the dealer with something he can get his teeth into.

Initially I was disinclined to blame the Battery, but everything is pointing that way and as time goes on I believe the discharge rate is increasing. The technician who tested the Battery wasn't exactly enamoured of the electronic tester he had. I'm a little suspicious that he tested with the Battery connected to the car, I would have thought this would change his measured internal resistance and any charge rate test the equipment applied. Does anyone know how it should be done.

[kithmo]

The rain on the door handles problem should only occur if the key is within 2.3 ft of the door, more than that and the key is out of range to unlock the doors.

Do you have any other wireless gadgets near the car, such as cordless phones etc ?

[MLW2233]

This is a tricky one as you could spend ages and a lot of money on diagnostics. A cheaper option would be to get a Bosch Silver 4 year guarantee Battery from Europarts. Click and collect on the web and get a 25% discount at the moment. About £50 and at least you have discounted a dodgy Battery. Charge it for about 4-5 hours at home first, and its easy to fit. How old is the present one?

I had all the usual 4 year iffy dashboard lights problem and locking problems on my Gen 2. The new Bosch solved everything. The central locking is a good diagnostic tool, as when the Battery is in top condition, you get a very strong chunk chunk noise when locking it and setting the alarm on the key. A dodgy battery gives a soft slue slue noise, barely audible.

[zygot]

I had a Toyota Prius T Spirit which developed a problem with the 12v Battery. The car would take several attempts to get into the ready mode. Took the car back to the dealer which was still under warranty. The car performed perfectly whilst in the garage. They stated that no fault could be found. It happened again with another visit to the garage where I was informed that unless they witnessed the fault they would not do anything about it. I contacted the AA who told me that the Battery was discharging with not enough power to trip the starting relays. The trip to the garage was enough to charge the Battery up for the time it was in the garage and should have been tested under load. I gave all this information to the Toyota garage and their reply was ' we do not take into account third party opinions'. Needless to say when I now get a survey asking my comments on the servicing of my car I always reply I did not witness the service so I cannot comment.

[jonesbach]

Kithmo,

Perhaps I should downplay the effect of rain on door handles as when I made the association I can't be absolutely sure I wasn't still getting wireless interference and yes there are other radio sources not that far away. However, if they are affecting the car then I would expect more complaints shortly as I doubt I'm the only one in that situation.

MLW2233, zygot,

The thought of forking out for a new Battery has crossed my mind, but it does go against the grain given the cars age. It would save the agro that zygot reports, and I expect I'll get the same. It's almost as if the dealer expects the car to be perfect and can't believe you can have a problem.

I'm still not certain it is the Battery. I would expect its effect to be steady and perhaps slowly deteriorating. Over the last week that is how it was, but yesterday I did the same 40 mile trip as earlier in the week and today the voltage had recovered to 12.7V, something I haven't seen since I put it on charge.

[MLW2233]

Every time you go to the garage, the Battery charges up, and all looks fine to the mechanic. I have had absolutely duff batteries in old student cars that after a 3 mile run are perfect.....until the next morning. It is the ability to hold a charge that really defines a 'good' Battery. I have had batteries with 9 volts and plates not working, that will jump start and go for miles until you switch off and then nothing, totally dead. Given the stress that this entails, £50 may get your life back.

How old is the Battery? Even if it is new, it may have been iffy when it left the factory.

[MLW2233]

Just a thought. Plan B is to go to a proper auto-electrician and ask him to find the current leakage. In my experience these chaps are usually very specialized, fairly cheap, know their stuff, and do not like to say, 'sorry, I've no idea what is wrong'. They know electrics. Garages just replace bits these days.

[wass]

Just a thought. Plan B is to go to a proper auto-electrician and ask him to find the current leakage. In my experience these chaps are usually very specialized, fairly cheap, know their stuff, and do not like to say, 'sorry, I've no idea what is wrong'. They know electrics. Garages just replace bits these days.

The simplest way to check for a discharge is to fit an ammeter so that it may be seen through a window onto the positive line from the Battery and progressively remove and replace the fuses one by one , noting which ones show a drop in current on the ammeter. There will be "sleeper" circuits such as the in car security which will be a constant drain. As MLW2233 says, an accomplished electrician will not struggle at all with this. There are comparatively simple to operate and relatively foolproof Battery testers around these days which are used by the breakdown services (AA,RAC etc) and most servicing organisations which would sense a duff Battery within minutes; an accomplished auto electrician would have one of these too.

[jonesbach]

Can I give some final feedback on this problem in case it is of help to others.

NOTE: All voltages given below were taken at the Battery.

The problem was caused by the Battery only taking a limited charge. Whether this was caused by cell voltage imbalance, acid stratification, sulphation or a combination of these I cannot tell. My reasons for believing this are

1 I monitored the car charging voltage on several occasions. With the Battery indicating ½ charge(12.3 volts), charging cut back to trickle as soon as a surface

charge had developed(usually within the first 2 miles of the journey).

2 With a 'full' battery, powering up without pressing the brake(allowing background load, fan, radio, etc. to discharge the battery) caused the voltage at the battery to drop to 12.0 volts in less than 10 minutes. On recharge it quickly switched to trickle charge.

My experience of erratic, but rapidly decreasing voltage was just a symptom of this.

To cut a long story short I purchased a CTEK CTE-MXS5.0 5A Car Battery Charger. This intelligent charger has a recondition mode, so I disconnected the battery and put it on this program. It quickly reached the 'RECOND' stage, but then repeatedly cycled between this and 'ABSORPTION' and this continued for 18 hours(Suspended overnight at 12 hours). CTEK have confirmed that this is what they would expect if the electrolyte was stratified.

On reconnection I again tried discharging the battery and this time it lasted 15 minutes(headlights on 5 minutes), but when I put it back on charge it took over 2 hours to reach trickle charge; much longer than previously. This looked promising so I again discharged it, this time to 11.8 volts. It took 45 minutes to discharge with the headlights on for 20 minutes, and it then took over 6 hours to recharge. The battery is now holding its voltage at around 12.6 volts(12.55 under light load) and has done so for over a week even when the car was idle for 2 days. I don't suppose the battery will ever return its factory condition, but at least it is usable. I'll just have to monitor it and give it another recondition should it become necessary.

Observations

I suspect the battery doesn't like the regime of trickle charge/discharge that it is getting though why it should happen to my new battery is unclear unless, as mentioned in a previous reply, it had already spent a long period in storage. I have wondered if I somehow have the wrong battery in the car. Does anyone know if the battery is a deep cycle or just an 'ordinary' starting battery and how would you tell the difference?

CTEK advise that the charger should be used on a regular basis and yearly to recondition the battery. They say it WILL(not can) lengthen battery life. I note that there are a lot of prius drivers out there who are not getting a long life from their battery. If you are in this position, I recommend you try this charger, it's the best purchase I've made since buying the car and when I bought it from Amazon it was under half the price of a new battery. I still think that the car was a good purchase even though Toyota have done their best to disabuse me of this.

Thank you all for your advice, it was most helpful.

[MLW2233]

That is interesting, but gosh, so much hard work and a posh Battery charger that is great but........

Again I ask how old is the 12 volt Battery? For £50-52 all you problems go away for 4 years.

My Bosch sliver Battery is still great after 9 monthsish. Every time I lock it it is a strong chunk chunk, and ...... so far it 'feels' so strong and reliable.

Just buy one.......really.

[jonesbach]

MLW2233, I looked at replacing the Battery, but as far as I can tell Toyota have it sown-up. If I want the 'official' Battery it has to come from them, and if you don't use the official Battery you can probably wave goodbye to your warranty on electrical faults. This is not necessarily what I expect Toyota UK may say, rather it reflects my experience of the local dealer and Toyota's response. If the dealer chooses to say a problem has been caused by 'X', Toyota will back them up. You are left with the impression that you are the pink bit stuck to the steering wheel and the only recourse you have is in law and that will prove very expensive.

When the car is 5 years old I'll definitely be taking that path, but until then, I know when I am over a barrel!

[Aceshigh84]

I can't believe that the dealer hasn't replaced (or won't replace) the Battery under warranty, especially if presented with the findings of the meter tests.

I would not expect to have to either replace a Battery myself or go through the hassle of charging it on a new car. I only had to replace the Battery on my Accord once, and the car was 12 years old and has done over 160k.

Call me naive, but a 5 year warranty to me means that anything at all that goes wrong gets fixed or replaced by Toyota at no cost to me - unless of course it was actually my fault.

[MLW2233]

I did not know it was still in guarantee. A Battery is hardly a wear and tear item. I have had 'normal' batteries last 10 years. New ones are much better than those in the 1960s and 70s. It should be a warrantee job.

[jonesbach]

Aceshigh84, MLW2233,

You have both put your finger on the real issue. OK my Battery may be a special case, but having previously owned a Toyota Corolla for 14 years(new Battery at 12 years/100,000+ miles) I find it ridiculous that a Battery only lasts four years. Either Toyota have gone downhill in a big way since I bought the Corolla or there is a design fault.

I get the impression that Toyota are caught in a mind set that they build good cars therefore there can be no problems. Anyone who raises an issue is a troublemaker. I have seen that lack of empathy when dealing with customers in my own contact with them and reading other threads on this forum gives me the impression I was not the only one to experience this.

[MLW2233]

That is a good observation. One does feel that the customer is the problem, not the issue. Like you I have had batteries last 10 years, in fact, 8-10 years on most cars seems to be the norm nowadays. I can't understand why the Prius has a 4.5 year life and then a whole host of problems appear. It is smallish, but my old Hillman Imp Battery as a student was only a tad bigger and had a real job to start a 10:1 compression engine. It would be interesting to see who has the longest lasting Bosch Battery? What can they do?

[timberwolf]

I would say there are many more electronic device still active in a modern car (even when it is sleeping) than in any of the cars that you mention. Apart from the obvious alarm and key fob entry, on the Prius the brake system is live even when the car is off (the pump to re-pressurize the system will activate after opening and closing the driver's door).

The handling of the brake fiasco on the introduction of the Prius Gen 3 was very revealing about Toyota GB and their attitude towards their customers, it absolutely stank. Given their attitude it isn't surprising that their franchised dealer network is pretty poor.

But I have had 12V Battery and electrical problems on other makes of car, and dealers are useless irrespective of brand. It doesn't help that they rely on those snake-oil testing tools that invariable give a positive result only for you to go home and have exactly the same problem again after the Battery has rested.

[Guest]

1330 hrs sunday 10/11/13

Just went to get my 2013 Auris excel Hybrid out of my garage and for the 2nd time this year the smart entry is not working or the fob, immobiliser light is flashing as normal inside,

the illumination inside that normally indicates you are in range, did not occur, I thought not again,

tried both key fobs, and manual using fob, left mobile in house, to confirm no wireless issues clashing, I had a good run on Friday used wipers lights etc as normal,thats was the last day i used the car, its always raining so i fail to see why this would be an issue as the last time it was dry,

I have called Toyota assistance AA who are sending an agent as their patrols are busy, lets hope he can identify what the issue is, as the AA could get the car started last time but no reason why it happened.

Ive owned many Toyotas and this one has now had more breakdown calls than all the others put together the only problem i ever had with them was a heater - fan unit in a 59 plate Avensis that was faulty and wouldn't blow.

Toyota you monitor forums, what are you doing about this issue

regards John

[MLW2233]

They really do seem to have a problem with the 12 volt batteries that is all out of proportion to the solution. OK, a small Battery is good for weight and mpg, but lets get real. In January at minus 6 degrees you want something beefy. If the charging system tends to go into trickle mode compared to a normal car, then the solution is a bigger Battery. Big = reserve power. Big also = cheap solution. Since I fitted my Bosch Silver £52 Battery I have had not a shred of concern, even after 6-7 days not using the car.

[RunningInPleasePass]

1330 hrs sunday 10/11/13

Just went to get my 2013 Auris excel Hybrid out of my garage and for the 2nd time this year the smart entry is not working or the fob, immobiliser light is flashing as normal inside,

the illumination inside that normally indicates you are in range, did not occur, I thought not again,

tried both key fobs, and manual using fob, left mobile in house, to confirm no wireless issues clashing, I had a good run on Friday used wipers lights etc as normal,thats was the last day i used the car, its always raining so i fail to see why this would be an issue as the last time it was dry,

I have called Toyota assistance AA who are sending an agent as their patrols are busy, lets hope he can identify what the issue is, as the AA could get the car started last time but no reason why it happened.

Ive owned many Toyotas and this one has now had more breakdown calls than all the others put together the only problem i ever had with them was a heater - fan unit in a 59 plate Avensis that was faulty and wouldn't blow.

Toyota you monitor forums, what are you doing about this issue

regards John

Sorry to hear about your problem Battery John, I have had the self same problem, see:

http://www.toyotaownersclub.com/forums/topic/151089-battery-has-discharged/

Take the car back to your dealer and insist they change the Battery, they will say your Battery is okay and only needs to be charged, but insist the battery has to be changed, they will tell you they do not have one, so ask them to take one off a new car so you can be on your way with minimum inconvenience.

[Guest]

Cheers Kevin as it happens Im changing to a new diesel Auris this week, so hopefully won't be plagued by this annoying issue, i had already planned to change car as I'm not impressed with the Hybrid overall and this problem is widespread, an agent from a garage attended this afternoon and he was in a recovery truck, he wanted to push the car out of the garage then use his extra long jump leads to jump it, I questioned his technical ability and he admitted he has no Hybrid knowledge, which I had asked the AA to make sure that the attending garage was competent

He called his control as I Insisted the AA attend as their patrols are trained on these Hybrids,

AA arrived 20 mins later

Result attending AA patrol did exactly the same as the last AA guy did in July when he attended and now it all works, he advised possibly needs longer runs, yet I did a 20 mile trip on Friday each way, he said symptons point to flat Battery as if lights had been left on, although that weren't , I would admit that if it was the case, I even switch them off if they are on dusk sensing mode when I park up, no interior lights were used on my last trip or the boot opened either, when I shut the garage door all the interior lights were out and the mirrors folded in.

[RunningInPleasePass]

I think your problem is simply a duff Battery, but as you are changing it soon I suppose it's not worth bothering too much.

I'm surprised you don't enjoy the hybrid, but I suppose they don't suit everybody, but if you only do a low mileage are you sure that the diesel is the best choice?

Kind regards

Kevin

[timberwolf]

Simply? I don't recall this many 12V Battery problems on brand new cars for the Prius Gen 2, Gen 3, or the Auris Gen 1.