Battery being drained

[Stafkel]

As any one had similar experience I have a 2001 VU SS ute GEN3 lately the battery is being drained over night to a stage where it will not turn the motor over. I have slow charged the battery put it back in and within two days same problem. Last check when idling the alternator was putting 14.49 volts in so I disconnect the battery leads and test the voltage in the battery it was 12.99v next morning I tested the battery it was 12.89v
connected the leads and the next bay the battery was 11.97v. any ideas before I head to the sparky for help.

 

[97VTSS]

As any one had similar experience I have a 2001 VU SS ute GEN3 lately the battery is being drained over night to a stage where it will not turn the motor over. I have slow charged the battery put it back in and within two days same problem. Last check when idling the alternator was putting 14.49 volts in so I disconnect the battery leads and test the voltage in the battery it was 12.99v next morning I tested the battery it was 12.89v
connected the leads and the next bay the battery was 11.97v. any ideas before I head to the sparky for help.

How old is your battery??? Because even an old battery will hold charge to an extent, but will take very little to discharge it.

 

[Wombles]

Have you done a load test on it? Find out what it drops to. Might be a crook battery.
How olds the battery? They usually get replaced every 3 years.

 

[97VTSS]

Have you done a load test on it? Find out what it drops to. Might be a crook battery.
How olds the battery? They usually get replaced every 3 years.

Yeh.... A load test good idea. Charge up the battery fully, then put a load on it, say.... turn your headlights on, just low beam will do and put a voltage meter on your battery, time it and see how fast the voltage drops over a given time. If for example you have an 80 amp hour battery at full charge, it should take 1 hour to drain the battery with an 80 amp draw.....2 hours @40 amps, 4 hours @ 20 amps and so on. So if your low beams total wattage is 110 watts (55 watts each). Divide the 110 by the voltage which is 12 = 9.1 amps. So about 8 hours. If the battery has been charged and discharged alot it will ruin your battey and it wont hold charge. They are not like deep cycle batteries and are not designed to be discharged and recharged alot.
Pretty sure that's how it works. Please correct me if i'm wrong.

 

[Stafkel]

Thanks for the advise
Replaced battery after a mate check the old one he said the same as you the battery was crook showing over 12v before starting pulling down to 10v when trying to start. Now starting fine with new battery

 

[97VTSS]

Good to hear everything is fine now.