Good/bad batteries or parasitic drain?
Discussion
Hi all.
I have a Toyota HiAce 2.5 D4D
It has two (never really known why?) 70ah batteries.
If I don't use the van for a week or two I can find the batteries are flat.
I take them off, charge them fully and leave them off for a couple of days to see if they hold their charge.
They appear to hold their charge well.
I was under the impression that if they were bad they would lose their charge?
If my assumption above is correct, could it be a parasitic draw?
Either way, could someone tell me, or point me to a tutorial on, how to do a full (ish) test?
I have a multimeter should it be needed.
Cheers.
I have a Toyota HiAce 2.5 D4D
It has two (never really known why?) 70ah batteries.
If I don't use the van for a week or two I can find the batteries are flat.
I take them off, charge them fully and leave them off for a couple of days to see if they hold their charge.
They appear to hold their charge well.
I was under the impression that if they were bad they would lose their charge?
If my assumption above is correct, could it be a parasitic draw?
Either way, could someone tell me, or point me to a tutorial on, how to do a full (ish) test?
I have a multimeter should it be needed.
Cheers.
Ok, so a bit more confusion for me.
I've just taken the batteries off.
I thought I'd test them before starting the charge.
One is reading 13.02 the other 13.03, the van hasn't moved for a week or so.
Why would they both read higher than the 'required' 12.6 but fail to turn the engine over?
I've just taken the batteries off.
I thought I'd test them before starting the charge.
One is reading 13.02 the other 13.03, the van hasn't moved for a week or so.
Why would they both read higher than the 'required' 12.6 but fail to turn the engine over?
Right, I can answer you now, I was limited to 5 posts!
Note to site owners, it would be good to make it clear that newbies only have 5 posts for the first 24hrs.
I didn't realise until I tried to reply last night (of course, I could have missed it and they do tell you?)
Plus, it would be good if when you reply you can see the thread you are replying to rather than have two tabs open.
Just sayin'!
ARH, I've done that before and it bumps with no issue.
It only needs a slow roll and a slight bump and away it goes.
E-bmw, I've been on to the place I bought them from and they say they just sound like they've had it.
I had a new alternator a while back and he said a dodgy alternator can damage batteries.
Plus they are around 7 years old.
I'll recharge, drive to the battery place and get them to test them.
At £80 a pop I'd rather not replace them (I'm very likely selling it in January) but hey!
Note to site owners, it would be good to make it clear that newbies only have 5 posts for the first 24hrs.
I didn't realise until I tried to reply last night (of course, I could have missed it and they do tell you?)
Plus, it would be good if when you reply you can see the thread you are replying to rather than have two tabs open.
Just sayin'!
ARH, I've done that before and it bumps with no issue.
It only needs a slow roll and a slight bump and away it goes.
E-bmw, I've been on to the place I bought them from and they say they just sound like they've had it.
I had a new alternator a while back and he said a dodgy alternator can damage batteries.
Plus they are around 7 years old.
I'll recharge, drive to the battery place and get them to test them.
At £80 a pop I'd rather not replace them (I'm very likely selling it in January) but hey!
Sorry for any confusion.
I have both bumped and jumped, both resulting in the van starting with ease.
It's been a bit of a crazy day trying to test anything today.
A car rolled down the hill, hit our neighbours wall, knocked it over, which hit our car, so I've been clearing debris off the drive and speaking to scammers, sorry, insurance companies.
I have both bumped and jumped, both resulting in the van starting with ease.
It's been a bit of a crazy day trying to test anything today.
A car rolled down the hill, hit our neighbours wall, knocked it over, which hit our car, so I've been clearing debris off the drive and speaking to scammers, sorry, insurance companies.
Thanks for all the contributions.
Update.
I went to the battery bloke yesterday, he told me the true age of the batteries from a date on one and a code on the other.
One is 2017, the other.............2013!!!!!!!
He 'tested' my batteries and the printout stated they were both good.
Thing is, as I was driving back home I thought, hang on, they are wired parallel.
He didn't isolate them, so any reading is across both batteries, so that was a waste of time.
So, this morning I spent a while testing. Thanks for the link kestral, that is what I was after in my first post.
With batteries wired parallel, both batteries were at 13.25, no surprise as they are still connected.
Isolated, the 2017 read 13.25, the 2013, 13.20, likely because the older battery is parasitic and taking charge from the 'better' battery maybe?
So I tried to start the van using just the 2013, there was a pathetic shrug, but didn't turn over once.
I tried the 2017 battery on its own, it started the van, but with a struggle, as would be expected anyway as it really needs the two.
I tried load testing just the 2017 battery.
Read between 15.06-15.17 running.
Starting produced a 09.25 ish reading, and it would start 3 times in quick succession with the reading lower each time.
I don't think it would have started a fourth time.
With both connected, running the reading was 15.30.
First start was 10.53, then around 09.75 - 09.24. I did four starts in quick succession, so a positive result.
Conclusion, the 2013 battery has had it, although it is adding that bit of extra oomph needed, until it gets tired.
The 2017 battery is, I think, at around 85% good, so I need one battery.
All contributions have been much appreciated as I've learned a fair bit.
Oh yeah, the battery guy, despite his faux pas with the testing, had some interesting stuff to tell me.
They supply BMW with batteries, and he told me BMW have complained to them because their batteries are lasting too long, which is affecting their after sales. Wow!
He also told me about two batteries that are sold, one I forget the make of the car it was for, but it costs in the region of £350, the other is for a Porsche, and that costs around £550, yet both batteries are identical. Disgraceful behaviour all round.
Anyway, all that stated, I now have a red light with a key symbol flashing on the dash. Aaaarrrgghh!
Update.
I went to the battery bloke yesterday, he told me the true age of the batteries from a date on one and a code on the other.
One is 2017, the other.............2013!!!!!!!
He 'tested' my batteries and the printout stated they were both good.
Thing is, as I was driving back home I thought, hang on, they are wired parallel.
He didn't isolate them, so any reading is across both batteries, so that was a waste of time.
So, this morning I spent a while testing. Thanks for the link kestral, that is what I was after in my first post.
With batteries wired parallel, both batteries were at 13.25, no surprise as they are still connected.
Isolated, the 2017 read 13.25, the 2013, 13.20, likely because the older battery is parasitic and taking charge from the 'better' battery maybe?
So I tried to start the van using just the 2013, there was a pathetic shrug, but didn't turn over once.
I tried the 2017 battery on its own, it started the van, but with a struggle, as would be expected anyway as it really needs the two.
I tried load testing just the 2017 battery.
Read between 15.06-15.17 running.
Starting produced a 09.25 ish reading, and it would start 3 times in quick succession with the reading lower each time.
I don't think it would have started a fourth time.
With both connected, running the reading was 15.30.
First start was 10.53, then around 09.75 - 09.24. I did four starts in quick succession, so a positive result.
Conclusion, the 2013 battery has had it, although it is adding that bit of extra oomph needed, until it gets tired.
The 2017 battery is, I think, at around 85% good, so I need one battery.
All contributions have been much appreciated as I've learned a fair bit.
Oh yeah, the battery guy, despite his faux pas with the testing, had some interesting stuff to tell me.
They supply BMW with batteries, and he told me BMW have complained to them because their batteries are lasting too long, which is affecting their after sales. Wow!
He also told me about two batteries that are sold, one I forget the make of the car it was for, but it costs in the region of £350, the other is for a Porsche, and that costs around £550, yet both batteries are identical. Disgraceful behaviour all round.
Anyway, all that stated, I now have a red light with a key symbol flashing on the dash. Aaaarrrgghh!
Griffith4ever said:
You've got odd readings there without explaining when and how you took them.
"Isolated, the 2017 read 13.25, the 2013, 13.20, likely because the older battery is parasitic and taking charge from the 'better' battery maybe?" - How long did you wait before taking the readings? because they are meaningless if taken immediately after being charged. You need to wait a good 30 mins, - 1 hour to be sure. )Neither battery will be "charging " the other once pulled off charge - they'll eqialise a bit but they are both settling back to 12.6v
2013 - bin it, just based on age alone.
"it started the van, but with a struggle, as would be expected anyway as it really needs the two." - I very much doubt it - you have 2 probably for cold weather (Japanese van). I don't know the specs of your batteries but even a 70Ah battery should start most engines fine. More likely your 2018 battery is on the way.
.
"Read between 15.06-15.17 running." - that's very damaging overcharging - your alternator regulator is shot.
I'd bin both batteries tbh. Even your 2017 is 8+ years old.
As stated previously, they have been off the van on other days for up to 48 hours and read similar."Isolated, the 2017 read 13.25, the 2013, 13.20, likely because the older battery is parasitic and taking charge from the 'better' battery maybe?" - How long did you wait before taking the readings? because they are meaningless if taken immediately after being charged. You need to wait a good 30 mins, - 1 hour to be sure. )Neither battery will be "charging " the other once pulled off charge - they'll eqialise a bit but they are both settling back to 12.6v
2013 - bin it, just based on age alone.
"it started the van, but with a struggle, as would be expected anyway as it really needs the two." - I very much doubt it - you have 2 probably for cold weather (Japanese van). I don't know the specs of your batteries but even a 70Ah battery should start most engines fine. More likely your 2018 battery is on the way.
.
"Read between 15.06-15.17 running." - that's very damaging overcharging - your alternator regulator is shot.
I'd bin both batteries tbh. Even your 2017 is 8+ years old.
Edited by Griffith4ever on Friday 7th November 16:15
They took a fair while to reach 12.7 but neither ever fell below, which puzzled me further.
The 2013, I agree.
In regards to the 2017 battery, if you read on, it started the van 3 times in quick succession, which isn't bad for a battery that may be at 85%.
I likely thought it sounded a struggle as I'm used to the two battery scenario.
On the overcharging likelihood, you can get such a reading from bad batteries, from what I've read, so not necessarily a dodgy alternator.
As I've stated, I'm likely selling it in the new year (but I've said that before, so I'll probably still have it this time next year) so if one is showing good - 85%, I'm reluctant to bin it and buy two. Plus, don't forget, we need to save the planet!
That's my excuse anyway.That said, the guy said I could have two for £140 instead of £80 each, so...
Went out in it 2 days ago so it's been sitting for around 48hrs.
Just took a reading now and it was 13.12.
Starts like I've got new batteries, at the moment.
Not had time to get new ones/one yet as dealing with the car insurance (see 5th November post), which is more of a pain than my battery issue.
Just took a reading now and it was 13.12.
Starts like I've got new batteries, at the moment.
Not had time to get new ones/one yet as dealing with the car insurance (see 5th November post), which is more of a pain than my battery issue.
I've asked my nephew to drop his off.
I could have tried mine on my car battery but that's been taken for repair.
I have tried a 1.5v AA battery and it reads 1.72, which brand new and under no load seems correct.
I have a LAP multi meter that is now showing the battery sign, meaning new battery required.
Batteries batteries everywhere, what would we do without them!
I could have tried mine on my car battery but that's been taken for repair.
I have tried a 1.5v AA battery and it reads 1.72, which brand new and under no load seems correct.
I have a LAP multi meter that is now showing the battery sign, meaning new battery required.
Batteries batteries everywhere, what would we do without them!
New battery in the multi meter.
Now showing correct readings.
1.72 for a 1.5v aa alkaline would be unusual, granted, but 1.6v or just over is very usual for a fresh 1.5v aa alkaline.
My nephew's (different model and 'better' than mine) read similar.
I shall return to the battery geezer, remove the leads so they are isolated, ask him to test them again, and, depending on the results, return with one or two batteries.
I have learnt several things regarding testing, also that a multi meter can give a false reading because it's battery is low, and other such interesting stuff.
I will let you know how many batteries I purchase and probably test them, just because I can.
Now showing correct readings.
Griffith4ever said:
hehe - no, it should read 1.5v. Your meter battery is dying. Absolutely no way a 1.5v AA would ever read 1.72v. It woudl read 1.499 / 1.5v. (I test them often).
Griffith, hehe back. You are correct, and wrong. 1.72 for a 1.5v aa alkaline would be unusual, granted, but 1.6v or just over is very usual for a fresh 1.5v aa alkaline.
littleredrooster said:
Am I the only one who suspects an over-reading voltmeter here?
littleredrooster was the one that came up with the possibility that my meter may be giving false readings, so kudos to he/she.E-bmw said:
They can occasionally get to 1.6 v when brand new & straight out of the pack but never known more than that personally.
Alkaline that is, rechargeable batteries are more like 1.2v
E-bmw, correct, that is similar to my reading of 1.615 - 1.616 now.Alkaline that is, rechargeable batteries are more like 1.2v
My nephew's (different model and 'better' than mine) read similar.
I shall return to the battery geezer, remove the leads so they are isolated, ask him to test them again, and, depending on the results, return with one or two batteries.
I have learnt several things regarding testing, also that a multi meter can give a false reading because it's battery is low, and other such interesting stuff.
I will let you know how many batteries I purchase and probably test them, just because I can.
I went back to the battery depot today.
I parked up and disconnected one of the batteries so they were isolated.
In the words of the bloke who tested them, the 2017 battery is f*#@ked and the 2013 battery is really f*#@ked, giving a reading of around 160amps when it is meant to be 600!!
So two batteries were purchased, and at £70 each for 70ah batteries, not bad.
It turns over so fast now that it's a wonder the alternator doesn't fly of it's housing.
Thanks all for the learning curve and passing on your knowledge.
I parked up and disconnected one of the batteries so they were isolated.
In the words of the bloke who tested them, the 2017 battery is f*#@ked and the 2013 battery is really f*#@ked, giving a reading of around 160amps when it is meant to be 600!!
So two batteries were purchased, and at £70 each for 70ah batteries, not bad.
It turns over so fast now that it's a wonder the alternator doesn't fly of it's housing.
Thanks all for the learning curve and passing on your knowledge.
Edited by PelicanHead on Wednesday 19th November 14:43
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