Sy5

iTrader: (6)

My battery was flat again today. Only 4 weeks old and the second time it's let me down, Last time was a week ago. I took it off and started charging it, after a couple of hours I took it off charge (still flat according to charger) and tested it with a multi meter (not sure if I'm doing it right mind) and got 12.4 volts! Surely this is fully charged?

I'm buying a decent charger tonight as mine is a bit old and I'm not sure it's ok for my calcium battery. But the one I have say's the battery is flat.

Would the wrong charger damage the battery or not fully charge it?

Could my problem be with something else?

Been driving with lights on for the past week and it's only been stood for 2 days.

joz8968

iTrader: (13)

You must have a/some parasitic drain/s, I would have thought i.e. drawing direct from the battery (no switches to the ign.), when the engine's off and the car's stood.

Charging a battery and it showing 12+ V isn't necessarily a sign that it's back to full, and reserviceable health. It's a bit of lottery whether a discharged battery can be successfully resurrected from the dead. Some will; some won't.

Spencerdale89

could not be charging.. have you put a multimeter across the battery with the car not running and see if it increases when its running? should be around the 14v mark when started,

joz8968

iTrader: (13)

Indeed. Try checking the alternator's output voltage with the engine running.

If way below 13.5-14.5V, then suspect faulty alternator. And having the lights on would indeed exacerbate a faulty alternator i.e. the batt. becoming even more discharged than it otherwise would.

Sy5

iTrader: (6)

Cheers chaps. I'll try above when battery is back on car. My new charger is on the case and say's battery is low but not fooked. It may not of been charged properly last time with the old charger but I agree I have a drain somewhere. I suspect the tracker and Subaru are happy to unplug it when the car is with them.

joz8968

iTrader: (13)

Is the charger you're getting got a trickle/slow charge feature? If so, defo use that mode...

360ste

iTrader: (1)

If I don't use my scooby for 10 days or more I have to charge the battery. The battery is quite small so the addition of and alarm, tracker and other bits we add on top of the clock and radio will flatten the battery. With the battery on the charger you want to be seeing over 13.5 volts on your multi-meter. The one I have only charges upto 13.5 volts then switches into maintain mode, this allows me to not bother disconnecting the battery so keeping all radio and other settings okay.

Sy5

iTrader: (6)

Yeah it is. First and last part of the charge is very slow.

http://www.halfords.com/webapp/wcs/s...5205&langId=-1

joz8968

iTrader: (13)

Cool.

It's a smartcharger/conditioner. You're fine then.

Sy5

iTrader: (6)

I hope so mate. :-)

Sy5

iTrader: (6)

Just an update. Battery went back on the car Saturday. 13.5 stood. Engine running 14.5. After a trip I retested it and it was 13.1. Yesterday tested again and it was 12.6. I did go for a run on Sunday and it was pissing down so lights/wipers all on. Today it's 12.55.

I checked for a drain and found a broken wire on the air con which seemed to be drawing 1amp. Also I got a reading from the block between the alt and air con pump of 4 amps. I disturbed a couple of earth points and it seemed to stop the draw. I'm a bit of a novice so I may be checking things wrong or taking readings from the wrong places...

I'm hoping it'll last this week and then Subaru can sort it out Monday.

Sy5

iTrader: (6)

It's looking more and more like a bad engine earth has been the cause of all my problems.

Car has been fine this week.