R3KogHyZe

Left my Civic with the headlights on for approx 90 mins at 5C outside temp whilst in an appointment. There was not enough juice to start the car on my return. Tried cranking it a fair number of times letting it rest every few goes.. got a jump-start off someone just came straight home.

What I'm wondering is :

Does this sound like a battery on it's last legs that I should definitely replace?

Is there a way to test the batteries performance with a multimeter?

To my limited knowledge that seems a bit quick to go flat, but it is 5C and most of my journeys have been short treks lately.

CraigW

iTrader: (1)

An hour and a half is quite a while with head & tails on..... not a huge battery to begin with.

Deep cycling does them no good.

Reverb2005

How old is the battery? More than a few years? Better just get a new one.

There is no way to test the capacity of the battery with a voltmeter. You can test the voltage. If you have not charged it yet and find the voltage is below 10 volts, it's probably toast.

Usually once a battery has fallen below a certain voltage threshold you destroy the internal chemistry of the battery. You could try charging it and you may actually get it up to 13 or 14 volts, but the capacity could be totally gone and as soon as you try to use the battery the voltage will plummet.

R3KogHyZe

Not sure of the battery age. I've had the car 20 months and it wasn't new then.

Great tip thanks !

After the drive home (7 miles?) I tested across the terminals (some hours later) and see 12.7v

DashCommand shows 12.2v

Tomorrow I will observe the voltage on the terminals whilst cranking, from my reading I understand it should not dip below 10v and should rise to 13.5-14v or so..

Wankenstein

1) Start car
2) Drive to autozone or other parts store
3) Tell parts-boy (liken to ****-boy..lol) you would like to have your battery, alternator and starter tested (no parts removed/all on car)
4) Report back here

emich

Mine won't last even 9 min. Still driving the car without replacing it.

mikey1

i dont think many batteries even when they are new would last 1.5 hours with head and tail lights on, especially in the cold,

if it charged back up to 12.7 and is starting the car fine i would just leave it