Battery keeps dying

I am having battery problems, if I don't start my car for 2 days the battery is dead I don't no what the problem is or what is daring the battery while its stood I have a new odyssey pc1500 battery really strong and powerful the alternator is in good working order and charging the battery ok, so I have come to the conclusion that somthing is draining the battery while its stood dose any body no why and what might be causing this also is there anything I can do to check or find a way to what may be causing this

Any help will be greatfull

Do you have an alarm / immobiliser ? ........ have you tried disconnecting the battery for a couple of days and see if its a dodgy cell in the battery and not something that may be draining it ?

It will be a bad earth somewhere. Clean the ones in the engine bay.
Then clean the ones on the rear lights. I think there's some there? Lol it's been a while.

As above bad earth or do you know how to check current draw? Do you own a multimeter ?

remove a battery lead with ignition off and all doors closed other than bonnet
lightly put the batt lead back on and see if you get a big flash as it touches the terminal, if so then its likely theres a major current draw somewhere which you can check by removing each fuse individually until theres only a light spark.
once you've found the fuse then see what that runs as it will be something on that circuit causing the drain

as said check all earths first though, alarms and immobilizers are the biggest culprits for current drain

Thanks guys will clean up all earth and I don't have an alarm fitted just an after market stereo, I did a search on parasitic drain it says to test battery draw by disconnecting the negative terminal and putting a multimeter on the negative lead and terminal and check draw I think under 0.25v is good correct me if am wrong and then pull each fuse out 1 at a time until draw drops is this correct
Will give this a go 2morow and see how I get on

yep more or less what ive just said above

Thanks bob will try this today and see if I can't find the cause

I had this same problem when i moved my battery to the boot,never solved it but never tried all the above either.

I'm mystified...
Why does a bad earth cause unwanted battery drain? I can see why a bad earth will stop things working but not sure about draining the battery...

Had this problem when I first had my pulsar, turned out to be the 6 disc cd changer in the glove box, whoever had fitted it had wired it up so they can listen to music without the keys in the ignition typical boyracers

johnboy wrote:
I'm mystified...
Why does a bad earth cause unwanted battery drain? I can see why a bad earth will stop things working but not sure about draining the battery...

to make sure the earth is actually an earth john and not drawing current from a live or chaffed wire somewhere.
ive seen some earths which have been showing almost 4v from an alternator where either windings have collapsed or bearings naff at standstill but when running they are working correctly

Ok so charged the battery fully so was showing 12.4v I disconnect the negative terminal got my multimeter put on negative cable and lead and was showing 12.4v so pulled each fuse out one at a time and the voltage didnt drop stayed at 12.4v so sum thing must stay continuously live by looks of it any one have any more suggestions I can try, I still need to clean up all my earth leads yet will do that 2morow

What auxcillarys do you have ie boost controllers .car stereo .etc ?

Have you tested the battery itself? Load test it. It may be new but it could be the problem. I work with batteries all the time and have known them to fail in less than a month due to an internal manufacturing fault.

I just have an after market head unit, turbo timer and a boost gauge that's it I've tested the battery and its good I have even swapped battery's for a good one which is in my brother sccoby and the problem is still there, when I come home and park car up and disconnect the battery if I come a week later and connect the battery back up it fires straight up but if I leave the battery connected and don't drive it for 2days the battery is dead

Scooby_killer wrote:Ok so charged the battery fully so was showing 12.4v I disconnect the negative terminal got my multimeter put on negative cable and lead and was showing 12.4v so pulled each fuse out one at a time and the voltage didnt drop stayed at 12.4v so sum thing must stay continuously live by looks of it any one have any more suggestions I can try, I still need to clean up all my earth leads yet will do that 2morow

so you connected one side of multimeter to earth cable and the other side to body earth and it was showing 12.4v?

if so I would suspect a dead short in alternator windings as that will draw full batt voltage as live is permenant

If thats the case cant you just disconnect the alternater and see if the battery holds charge .?

Yes bob disconnected negative terminal connected multimeter to battery negative terminal and other to body earth and was showing 12.4v? I will try to disconnect the power cable on the alternator and check multimeter readings again 2morow

Well it maybe worth a check mate if it is the windings as bob says by taking the wires off should rule it out .

Well you just have to love cars dont you, never a dull moment in pulsar ownership

Ok so disconnect the alternator power cable put multimeter on terminals again and still got same readings so that rules the alternator any more suggestions any one

I dont know anyone elses opinion engine bay side all thats left is starte motor soleniod but would think there would be a few tell tale signs if that was faulty .... have you checked the lives to the starter motor and alternater make sure its not chaffed against the engine and is shorting out ? ..

how I found out the disc changer was at fault with me was me dad was sitting in the car and when I connected the battery I could hear it resetting and clicking etc, so maybe get a mate and get them to sit in the car and connect the battery back and see if they can here any buzzing, or humming maybe worth a try.

hold on a minute......did you say you went from battery earth from multimeter to body earth?
if so then it will show batt voltage as your just affectively bridging the earth lol

you need ideally to check for amp drop with multimeter or voltage drop from + side iirc