The AGM battery on the BMW is the original fitted one and over 12 years old. We had problems with it during Covid due to lack of use but did the battery repair cycle on the NOCO charger and it’s still going strong
The agm on the wife's focus must be over 10 years old now. She inherited the car from me when I bought a new one in 2017 And I'd had it on their for a few years before then

Well, that's the kiss of death then!![]()
Sure I'm a young bloke, but what is that epsom salt treatment exactly?If you could get the bloody tops off and give them the old Epsom salts treatment it'd help. Worked a treat on the old lawnmower battery my lad sorted. The crud that came out was impressive.
I thought it had gone about 4 years back so ordered a new one. It's still in the box in the shedWell, that's the kiss of death then!![]()
That sounds like the wifes mazdaThe stop-start function hasn't worked for a long time now
After fitting the new battery it still doesn't work, but I'm not really bothered.That sounds like the wifes mazda
I can get that working IF I charge it fully with a proper Stop Start charger and we then do a journey of about 250 miles (can split into two x 130 mile journies. After that the stop start will work until she does a number of short journies in which case it stops working again
I tried a brand new stop start battery and that also needed a full charge and quite a few miles before the stop start came back
Methinks the parameters for the battery are set a bit tight
I'll hook it up to my Diagbox sometime and tell it it's been replaced.most vehicles these days, especially ones with stop start, need to be told they've had a new battery, its cca, and tech (sla, fla etc)
its actually dead easy with even a mid end scan tool.


I think the little indicator thing just shows its low in acid level as well as the charge state, its not a lamp just a little floaty ball I thinkThis reminded me to pull the battery from boys golf that he has not used for 3 months, not a peep from the ignition lights.
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Looks to be 5 years old, was showing about 9v on the meter, took over 24 hours on normal charge, now reading 12.9
The green indicator light has not come back so I am guessing it's goosed or cells have died.
Will stick it on the charger recondition setting and see but think I might be flogging a dead horse.
Yep my understanding also, I read they only read one cell so not really a measure of who goosed overall.I think the little indicator thing just shows its low in acid level as well as the charge state, its not a lamp just a little floaty ball I think
Agree it does seem a waste, what I read on the Yuasa site is "maintenance free" is the key, which most batteries seem to be now, which appears no easy or recommend or possibly even pointless way to maintain/recover them past apparent cell or cells death.Are modern cars batteries still lead acid inside?
Seems a waste not being able to get the tops off and have a go at cleaning them out.
I wonder if you could drill and tap the cells then fit plastic plugs...



