Curent drain

eddieboy · Oct 4, 2014

My car battery will go flat, if I leave it connected, within 2 days. If I remove the positive cable from the battery and reconnect after x amount of days it starts no problem.

When I put my multimeter in series it shows a drain of 0.11 amps. When I remove the fuses one at a time the only time this figure reduces is when I pull the battery fuse out.

So is my drain within the battery circuit? Or would the current flow be interrupted anyway?

Octopus · Oct 4, 2014

Sounds to me as if that something isn't switching off OR you are parked where lots of RF stuff is on!

What car is it?

Besoeker · Oct 4, 2014

If 0.11A drains your battery in two days, it suggests that your battery it knackered.

eddieboy · Oct 4, 2014

Murdoch said:
Sounds to me as if that something isn't switching off OR you are parked where lots of RF stuff is on!

What car is it?

Thanks for the reply. What do you mean by RF stuff?

It's a Mitsubishi Gto so about 22 years old.

eddieboy · Oct 4, 2014

Besoeker said:
If 0.11A drains your battery in two days, it suggests that your battery it knackered.

Isn't 0.11A a high drain then?

SJD · Oct 4, 2014

A current of 0.11A translates to approx. 2.5Ah over a day, or 5Ah over 2 days - if that drains the battery, then the nominal 40Ah or so battery can't be holding that much charge - on the other hand, that current seems somewhat high to me, I'd expect to be able to leave a car for 3 weeks and come back and it start.

Update after re-reading the original post: if pulling all the smaller fuses out doesn't change the current, then (a) are you sure you've found all the smaller fuses, sometimes they are in several locations, or (b) look at the wiring diagram for anything that doesn't have its own small fuse (starter motor?).

ayjay · Oct 4, 2014

i had the same prob on a stag
it was the starter solonoid
loads of carbon had built up around the main contacts
this allowed current to drain back thro the motor windings

Deleted member 72666 · Oct 5, 2014

eddieboy said:
My car battery will go flat, if I leave it connected, within 2 days. If I remove the positive cable from the battery and reconnect after x amount of days it starts no problem.

When I put my multimeter in series it shows a drain of 0.11 amps. When I remove the fuses one at a time the only time this figure reduces is when I pull the battery fuse out.

So is my drain within the battery circuit? Or would the current flow be interrupted anyway?

No, if so then it would make little difference when you leave the battery disconnected.

PEG · Oct 10, 2014

Have you a radio with a permanent live? Clock? Another one to check is your alternator.It is connected directly,and i have had them the cause of many a battery drain.You can meter,temp check or sometimes,it is easier to disconnect and measure. The first time i found this,i was fifteen years old,and my mates dad had a Bedford TK tipper with this issue.It had an early Lucas ACR alternator,and on a frosty morning,had proved flat again.On peeping under the cab (no tilt on these!) i noticed the only part of the engine without a dusting of frost,was the alternator! The minor discharge through the windings,heating them up just a tad.Your draw is quite low,so do properly load test your battery.