Battery Draining Fault

[Dan H]

Hi guys hope everything is fine and dandy. Ive got a problem with my j reg sw20 N/A. Somethings draining the Battery when the car is parked. I ran a multimeter test and found that when i unplugged the fuse marked DOME the multimeter wouldn't give a reading. i left the fuse out whilst i went to work and when i came back the car would start again, bingo, source of problem. Great i thought until i came to start the car up this morning. Battery dead. so unless there is something else draining the Battery then i haven't got a clue what could be wrong. The stereo blows its fuse too, could this be part of my problem? The guys at Halfords say that its charging up ok so i guess that rules out the alternator. Any help would be much appreciated because it is driving me insane (and i cant be late for work any more!). Thanks, Dan

[jimma]

Hi guys hope everything is fine and dandy. Ive got a problem with my j reg sw20 N/A. Somethings draining the battery when the car is parked. I ran a multimeter test and found that when i unplugged the fuse marked DOME the multimeter wouldn't give a reading. i left the fuse out whilst i went to work and when i came back the car would start again, bingo, source of problem. Great i thought until i came to start the car up this morning. Battery dead. so unless there is something else draining the battery then i haven't got a clue what could be wrong. The stereo blows its fuse too, could this be part of my problem? The guys at halfords say that its charging up ok so i guess that rules out the alternator. Any help would be much appreciated because it is driving me insane (and i cant be late for work any more!). Thanks, Dan

The draining dome (whatever that is!) might have harrassed your Battery into early submission!

[Scot]

Silly question, i know, but have you made sure theirs plenty of liquid in the Battery? On my old mans car, the boot light would never switch off, and of course how could he tell? might be somthing like that. Or how about a bad earth?

[Dame]

The dome is the collective name for the interior lights, cigarette lighter and radio (i think thats the lot...). Few questions.....

Have you tried removing the alarm fuse?

Is the barrery old? Has it been run down to flat several times?

If the Battery being charged properally? Voltmetre reading should be around 14.5V from the alternator when the car is running.

The alarm could be responsible for the power drain as could an old/regularly flatterned Battery. There could also be a wiring fault with the radio circuit etc.

Only real way to be sure is to remove each fuse in turn, to find the circuit causing the drain (of course you cannot remove any that are vital for running the car.....).

Don't forget there is also a fuse box inside the car, below the steering wheel, toward the bottom of the door - if that makes any sense.....

[The Case]

I'd echo the dud Battery idea- had similar probs with my SW20 - old batteries will seem like they charge ok when running, but it's whether or not they hold the charge that's the issue. Cell plates warp and corrode over years, and their surfaces are less likely to hold charge, which will dissipate over a few hours.

Get the cells checked out at you local tyre/exhaust/battery dealer, or see if there's a manufacturing date on the Battery (usually a sticker with cutouts or marks on the appropriate year/month). If it's over 4 years old, start there first before pulling any more fuses.

PS: I'm in the market for a 3S-GE crankshaft in good condition. I've posted a seperate forum.