VW Golf battery going flat

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Thu 27 Mar 2003 14:04
VW Golf battery going flat - CharlieB
I have a 20 month old Halfords HCB063 "heavy duty" battery in my 1999 Golf GTI (the VW battery lasted 30 months).
After parking the car for 4 days there's only enough in the battery to turnover the engine for a fraction of a second.

The car lives on a daily diet of two 14 mile, 1/2 hour runs a day. The battery voltage is 14.4V with the engine idling and 12.4 V with the engine off. The measured standby current drawn is 0.15 amps. Halfords won't give me a new battery as their battery tester says the battery is OK.

any ideas ??
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Thu 27 Mar 2003 16:59
VW Golf battery going flat - tonyt
Your residual current draw seems excessive which will cause the battery to go flat after a few days,it should be no more than 0.05 amps or less with everything switched off including all doors closed and interior light off with the exception of the time clock. Try checking the boot light to make sure it is not staying on with the tailgate shut,other than that something else is definitely causing the current drain.
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Thu 27 Mar 2003 21:07
VW Golf battery going flat - Railroad
Since you must have an ammeter, connect your it in line on the earth side of the battery and pull each fuse in turn until the drain disappears. Identify the circuit which that fuse protects, and you will have narrowed the problem down. Then disconnect each of the circuit's items in turn until the drain has gone, and hey presto you will have found it.

Don't forget also to disconnect the alternator just in case the fault lies within it.
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Thu 27 Mar 2003 21:15
VW Golf battery going flat - Peter D
I normally expect the 'standby' current to be no more than 35 millamps dependant on the alarm system fitted. Your volts are ok but can you measure the voltage whilst cranking, I think you have an earth problem or a heavily corroded briaded cable link between the pre-engage starter solonoid and the stater motor. Regards Peter
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Fri 28 Mar 2003 12:31
VW Golf battery going flat - Big John
Common culprit is the boot light, fold down seats to see if its still on with boot shut. cant remember the wattage of these bulbs. .15A X 12V= 1.8W thats quite a heavy drain...
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