New car battery showing 3.4v

Hi all:thumbsup: ,little insight :-well the bosses granddad has been stressed over his car battery(found out he only does 500 miles a year) but anyway he is old at 84 and i want his mind at rest.
I have tested his battery at 12.4v which to me is fine and only 3-4yrs old. Its only a 1.4 engine and a 44amp battery but short journeys with lights/heaters etc has all been explained. I have advised him to once a week ,keep it running once parked up with lights/heater off to allow some charge back into the battery.

As winter draws closer he is still worried as it can struggle starting so as rach has wrote her BMW off,i removed her almost new(and working fine) battery.

I am sure the brand is lion(not li ion :laughing: ) and its not a cheap one too.

Thats the story behind it today,now as he is hands on he was helping,i am not sure which order he connected (+ 1st or - ) certainly not connected wrong terminals!!! that is 100% sure. All fuses are fine as i checked them 1st...........

So i checked the battery,its showing 3.4v which is impossible unless something has "tripped" or faulted........

Has anyone heard of this,i have searched and cant find info, its as if a built in protection has just stopped power.

It can only be 1 of 2 things i can think
1- It is fubar
2-It needs resetting of some kind

Just to make clear,all terminals were secure which is N/A as i checked battery after removing on the pavement and showed 3.4v
.
Also i connected the removed 12.4v battery that did start the car........... via jump leads to the new fitted battery and dead,was hoping a reset of somekind i guess.........BUT no dash lights or anything as expected with 3.4v .

So it being even connected it stopped any current going from battery terminals..............

The original battery is now on and again imo its fine but 44amp is not the best and of course habits require changing no matter whats fitted:thumbsup:and again all i can do is advise on this of which i did.

But i want his mind at rest,as said he is 84 so piece of mind is critical as he lost his wife of 50+yrs last year so anything less to worry about is critical to me and of course his grand daughter Rach.

Any ideas or solutions are greatly appreciated in advance,i have a feeling the battery may just be dead,again its nothing major,will just buy another but its the of it all...............and battery is within 3 months old,started her BM the other day(after crash which damage etc is other side)on the button.

Sorry for waffle,just like to build a picture and give as much info as possible instead of" battery 3.4v why is it? " :laughing:

and to make things a little more odd i have just been out and tested battery again and now shows


6.9v

Regards ven:thumbsup:

I'm not sure what would have caused it, but I think this battery is absolutely knackered - time to get rid and replace it.

No correctly functioning lead acid car battery would read that low unless there was something seriously wrong. I wouldn't even bother putting this thing on a charger. Some chargers would not even attempt to charge when the voltage has dropped this low.

I suspect the reason for reading 3.4V initially was because it was connected to the car and some load was present. Later you measured the open circuit (unloaded) voltage, which was higher. However, an open circuit voltage this low almost certainly means that some cells within the battery have failed, so it's no good.

1. Could the Fluke be faulty?
2. Since it gets charged so infrequently you may want to consider an external battery charger like a Battery Tender. I have one and it is very easy to use. If the car is going to sit for awhile he could hook it up and it will keep the battery topped up. This would give him peace of mind that it will always be fully charged and the charger will never overcharge it. He also wouldn't have to guess how long to run the car to charge the battery.
3. If you get a battery charger then you could hook this one up to it and see what it tells you. If the voltage is too low then I believe that it won't try to charge it at all. This way you can be sure the battery is indeed dead.

I would try to borrow someone elses VOM and see what it reads. Depending on which Fluke you have it uses TWO batteries, a 9 volt rectangular and ?two AA or AAA cells. and you can't check your cells due to no power in the meter, the famous catch 22 issue. I have 1 VOM from the 5 buck barrel and 3 from the old RadioShack store beside the Fluke. 1 is nothing, two are the bare minimum for on the road mechanics or electricians. one might be lying to you !

Thanks guys for inputs,really appreciate, the MM is fine,the original car battery is 12.4 on MM which i measured at time,and its tested on other equipment too. But it maybe due a cell change so thanks for reminding me..............dont like leaving it too long.

As battery is not old i nipped around to garage as remembered they put new alternator and battery on at £200 a few month back. As i know them well(too well unfortunately ££££££££) no questions,got their tester out,showed "bad/replace" and 7.4v ,so he rang company there and then. New battery dropped off within 2hrs (nipped there at 3pm,got a call at 5pm to say its here)Not bad service is that

So new battery in boot,told her granddad and he is over the moon. Now i should be going now as dark,excuse to use flashlight :laughing: but as his battery is OK and its more a piece of mind,now 21:30 too.............job for tomorrow.

Happy ending,and thanks again for time replying,all they said really was they can just fail sometime............why/what caused it, i dont know

Thanks again:thumbsup: