Got a new dash cam but have been too busy to connect it up properly, so am manually plugging it in. I've managed to drain the battery twice leaving the DC plugged it. Now when I charge the battery to 12.5v, and put it on the car, before I even start it, it drops to 9v. Have I buggered my battery or might the be more going on?
I know I can get the battery load tested, but I live in the sticks and MrsZip is using her car.
Not sure if to just order a new battery (this one is 12months old), a battery booster or to call the mobile mechanic...
What's it plugged in to?
If you have a dashcam/adaptor with a tell-tale light, see if it goes out with the ignition being switched off. If it does then you have a problem elsewhere
If not, plug the DC in somewhere that is only "ignition live" and charge the battery
12.5V is an indication of a reasonably healthy battery, but you must measure it 24 hours after charging/driving to get a more accurate indication
9v - it’s dead a cell down , 12.5 is not a charged battery - you may be able to replace under warranty , I would no longer trust it especially with the proposer cold coming
Thanks guys.
The DC is manually plugged in the cigarette lighter, so I know when it's on, but forget to pull out somestime when I get home
There a lovely sticker on the battery telling me if it run below 6v the warranty is void.. which I suspect has happened. Then looking for the warranty (supposedly 3yr) to apply I needed to have "The guarantee is only valid for Bosch S3, S4, S4 E, S5 and S5 A passenger car batteries bought and fitted at Bosch Car Service Garages in the UK" which as I bought it online doesn't apply.
Battery is 1year +2 month old.
So what's a good make of battery? (that doesn't pretend to have a good long warranty)
Lookup voltage of a charged 12v lead acid battery , there is something called the float/surface charge up to 13v post charging that dissipates with a small load or hour or so , after that battery health without a load tester is guided by voltage and how long the voltage maintains - your 9v teading is indicating a cell no longer working
Anything from Tayna the Bosch was good , but all will be damaged by deep discharge
My normal online supplier BMS (normal, as in I've used them three times before), has a Hankook for £64 or Varta/Bosch for £85, is it worth trying to save the £20 or just go for the varta (**** bosch). I'm thinking lets not mess around but wondered..
PS: I have the wiring kit for the Dash Cam and will get that sorted asap
One with the longest warranty is a guide , even from the same manufacturer there are different levels of product - price usually gives an indication, although specialist suppliers may have stock to shift , personally I like yuasa but if you treat a really high quality battery badly it will kill it - if it’s a modernish car pay attention to the battery type as the battery management will behave differently according to battery type and depending on the manufacturer can cause issues- the battery codeing issues particularly bad on BMW for example.
varta. Have a web page with some good info - although slightly scary is good stuff to check if a battery is going to be replaced
search varta battery codeing BEM
for a useful intro