My van is a serial battery killer!

G'day.
Just wondering if anyone can shed some light on a little problem I've had with my van for at least 4 years now.

It's killed 3 or 4 batteries. It seems to keep discharging them when its left sitting for more than a few days.
I've checked parasitic current. Its about 30mA.
Is it possible that after a certain amount of time, drain goes up or something?
I just can't figure it out.

a newish battery should hold full charge for atleast a month if left connected and untouched
i assume u've checked ur charging circuit and made sure ur getting 13-14 volts when running
if all thats ok i'd check for some thing causing a drain
first thing to check is probably the stereo if u have a modern type fitted that needs back up
coz vws dont have an accesories postion i see so many with badly hooked up stereos
wired up to be live is bad as most of them dont power down completly when theyre turned off but wired to the ignition circuit is bad if u use it with the engine off as u'll fry ur points/ electronic ign module.

the other thing i had a mitsubishi express van (company car) years ago that did the same thing after a week the battery was dead
some clever knob head had wired up the spot light relay wrong so it was pulled in all the time
i could here it pulling in when ever i connected the battery and ran the battery flat in very short time

hth
-Joel

DUB74L wrote:a newish battery should hold full charge for atleast a month if left connected and untouched
i assume u've checked ur charging circuit and made sure ur getting 13-14 volts when running

Haven't directly checked it, but all signs point to it being perfectly functional.
Especially because that's the way I get the battery back to normal after using a charger to build up a starting charge.

if all thats ok i'd check for some thing causing a drain
first thing to check is probably the stereo if u have a modern type fitted that needs back up
coz vws dont have an accesories postion i see so many with badly hooked up stereos
wired up to be live is bad as most of them dont power down completly when theyre turned off but wired to the ignition circuit is bad if u use it with the engine off as u'll fry ur points/ electronic ign module.

Possibly. I don't remember the exact setup of the radio anymore. been too many years since I put it in. I think it's running from the fuseblock using its own fuse. I know it can be powered up while the van is off.
I remember the stereo had two powers. a standby and the main power.

the other thing i had a mitsubishi express van (company car) years ago that did the same thing after a week the battery was dead
some clever knob head had wired up the spot light relay wrong so it was pulled in all the time
i could here it pulling in when ever i connected the battery and ran the battery flat in very short time

hth
-Joel

Driving light relay is fine. That's one I'm sure of.
Although you did make me think of something. The aux battery relay. I'm not totally sure if itcould be the culprit though because the problems started way before I fitted it.

As I said in the first post though, the total parasitic current while the ignition is off is only 30mA. I know it's not much, but it is something though.

Thanks for your advice. You have given me some food for thought.

Are you running an alternator?
Could be a leaky diode.

Matt.

A 30mA drain should take some time to flatten a battery. This leaves only your charging system. I wouldn't assume it is ok - check it!