Battery Discharge

[manclad]

Does anyone know what the current drain is whilst the car is switched off?

Problem came to a head when the car wouldn't start after a 10 day stand.
I should add that the battery is about 6 months old and always turns the engine at a healthy speed.

I later measured the current drain and found it to be around 100mA, which seems a tad on the high side.

Any thoughts?

[delta925]

100mA equates to about 2.5 Ah capacity a day so yes high.

As to finding the cause I suggest is removing one fuse at a time to see if current drops. If removing fuses of the known permanently on items does not identify a group of components move on to items that should only be on when key inserted.

Worst case you will know the items not to blame.

[manclad]

100mA equates to about 2.5 Ah capacity a day so yes high.

As to finding the cause I suggest is removing one fuse at a time to see if current drops. If removing fuses of the known permanently on items does not identify a group of components move on to items that should only be on when key inserted.

Worst case you will know the items not to blame.

Thanks for the reply.

I borrowed a clipon ammeter yesterday and did some digging around.

At the battery terminal there are three cables connected to the terminal end.
One of these feeds the terminal block at the back of the dash, the other two disappear down the side of the engine, I assume to the starter and alternator.

The majority of current was down one the cables down the engine with nothing down the other and a small current to the back of the dash.

I should add that the clipon ammeter was built for high current readings, not milliamps, so accurate readings were impossible.

At this stage I assumed it was the alternator taking the current, perhaps a faulty stack, and left it for the time being.

Earlier today I separated the cables and measured them individually with a multimeter and found no current flowing in the two engine bay cables and only 50ma in the feed to the back of the dash.

After driving home I have just checked again and still only 50ma when all has settled down (it does kick in at about 250mA, then quickly drops to 100mA for a few seconds then dies down to 50mA).

So it looks like it was sticking at the second stage (100ma) and not dropping to 50mA, but all seems well at the moment but I will keep it under observation.

PS Sorry about the length of the post.