Battery Drain

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Sat 2 Aug 2003 21:08
Battery Drain - wonderwheels
Hi. My friend has a Fiat Uno K-Reg. Battery will go flat by the next day even after a full charge. Charged again today. Charger showed fully charged. Disconnected an put a meter across the terminals. The voltage just started dropping off. Within 3 minutes it was down to 7 Volts. Repeated the charge/test routine. The dropping off slowed down but it was still apparent. Battery isn't too old. All cells are OK with DI water. Fitted back to the car and checked the drain in series with the earth terminal (to earth strap). Showing 130 mA. Is that a problem?? Is the battery "duff"?
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Sat 2 Aug 2003 21:26
Battery Drain - Aprilia
Quiescent current should be 1/10, or less, of what you're seeing (i.e. 13mA or less) so you have a drain somewhere. Start taking out fuses one by one until you track down the problem circuit.

Notwithstanding the above, your battery is still bad. It should never drop to 7V after just 3 minutes. You need a new battery.
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Sat 2 Aug 2003 21:33
Battery Drain - StuW
Sounds like what my battery was doing. I flattened it by accidently leaving the interior light recharged it and it went flat again the next night. Kept repeating this proceedure until it wouldn't even hold a charge and it couldn't even turn the starter motor at all even after being leaving on charge overnight. Eventually decided to stop being a cheapskate (the battery was very old) and bought a new battery for £28 and got a three year guarantee with it. The engine fired into life instantly and have had no problems since. If the battery isn't too old and you still have the recipt you'll probably be able to get a new one for free!
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Sun 3 Aug 2003 10:18
Battery Drain - Peter D
Well your battery is well out it and your 130 ma is not good. A car with no alarms and no clock can be as low as 100 micro amps which is the leakage thru the recifier diode pack in the alternator. some alarms pull up 60 ma but 130 is a bit high but not the cause of the battery problem. Check things out and get back to the site if you need more help. Peter
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Sun 3 Aug 2003 10:27
Battery Drain - wonderwheels
Thanks for the advice.I am sure there are no lights remaining on. What is the best method of checking for the drain?. Removing fuses 1 x 1 as mentioned previously until the "rogue" circuit is found, or is there something more likely to be causing that sort of drain than another?.
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Sun 3 Aug 2003 19:35
Battery Drain - madf
Classic battery drain is the boot courtesy light: no-one can see it lit..

madf
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Sun 3 Aug 2003 19:56
Battery Drain - bazza
Did it drop to 7 volts when off the car ie disconnected? If so, it is an internal fault within the battery and you need a new one.

Baz
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Sun 3 Aug 2003 21:35
Battery Drain - Another John H
Light in the boot, or other courtesy light is usually 6 watt: about 500 mA.

The 140 mA quoted is likely to be the alternator - but it's still a relatively low drain:
to take 20 AH out of a battery will take about 6 days, if my calcs are correct, and you'll still start it during the summer if you have a half decent battery (say 45 AH fully charged).

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