Electrical Problem?

[ramzb]

Someone out there must be able to help pleeeese!!!
If I leave my fully charged battery connected, by the next morning it's completely dead, I've checked all the obvious things like lights etc, there is no alarm or i.c.e. fitted at moment as car is still in process of being rebuilt. But it is becoming a pain in the arse having to connect and disconnect the battery every time. Anyone got any idea what the problem could be?

[PukkaSilvia]

Sounds silly but maybe your battery is just nackered? check the water levels aswell as putting a multimeter on the disconnected battery at night and then rechecking it in the morning to see if what charge its lost whilst being disconnected.

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Check things like the interior boot light is switching off,maybe the alarm is not functioning correctly if you have one fitted, or maybe your cd player is not switching off properly and an amplifier for a subwoofer is staying on etc.

[ramzb]

I've tried a few different batteries, it's a brand new one on at the moment. Once connnected it'll only last about 4-5 hours before it's flat, leave it overnight and it's as if there is no battery.

[reece]

Hi m8'
Just a thought, Have you checked the boot light to see if it is turning off with the the boot is shut?

[ramzb]

Tried all the obvious things like lights etc, even pulled all the fuses and it still goes flat overnight, something is draining all the current but can't find out what.

[Dr Silvia]

Something is draining your battery thats for sure.. disconnect 1 battery terminal and use a multimeter to get a current reading with the ignition off. This will tell you how much current you are using with the ignition off.. not sure on what a 'good' reading would be but suspect under 3 amps

If that checks out fine then chances are its your alternator

Have you measured battery terminal voltage with the engine running? If it reads 12.5v then check the alternator output

terminal 'b' (+ve); measure the brown insulated terminal with 10mm nut to earth.. Should be 13.0 - 15.9v if not, its shagged