Battery drain in 1 week time

[sewell]

I'm Driving an E39 520i, my car battery drain in 1 week, i will use this car as a weekend car (this case happen 2nd time), can any sifu advise what normally gone wrong? my battery just change for 1 year only (DIN88 BOSCH S5 silver). the relay? electric component?SIFU please help

 

[champion]

You might want to check your alternator.

 

[Nik Mansor Mohamad]

It cud be yr alternator or some live wire left unattended .....get an experience wireman

 

[sewell]

my alternator is OK, i can jump start then everything back to normal. should be something relay or electric component.

 

[jarance]

when the car is shutdown, use a DC clamp-on ammeter across the positive wire at the battery. You should be able to see the current being consumed. If the current is greater than 1 amp, then there is a discharge which lead to the battery being drained of its electrical charge.

Alternatively, take the car to the battery shop. They have a battery tester which will discharge the battery and tell the state of the battery. A battery which is 1 years old do not means it is good. Sometime, the battery could be manufactured way before and kept on the shelf. It could be an expired battery as lead acid battery have a certain shelf life whether use or not.

 

[Vroom325]

Yes, according to my customer(our parts used in batter), the moment the battery is manufactured, the clock start ticking. Do take note, guys.