Drain on battery ?

[Cranfield]

Twice recently (second time this morning) I have had a flat battery when trying to start my Surf in the morning.
The contributing factor seems to be that I have had the tailgate open and a rear door for some time whilst loading the vehicle and sorting things out.
I did turn off all interior lights while doing this.

Both times I have been able to jump start fro my wife's car.

My question is , whats draining the battery ?
Surely if the lights are off its not using electricity.

I would add that I have no problems starting otherwise.

[pyemaster]

I would say your battery is knackered, I've had some in the past which would seemingly start the engine okay but struggle after a door was left open for a few minutes or the radio on. Sometimes they're on an edge, fully charged they have enough to crank the engine, but drain it just a little and they are too far gone.

Easy way to test it, borrow a battery from another vehicle and leave the lights on for a few minutes, until the point you'd be sure your current battery would struggle, and turn the key!

Owen

[Cranfield]

Thanks for the suggestion, thats worth a try.

I hope I don't have to replace any batteries, those things are expensive.
Be better not to open the doors for too long.
Still can't work out how the batteries drain with the lights off.

[pyemaster]

There are various trickle charges which can tip a battery on the edge over the edge - things like your stereo memory and dash clock...

Owen

[Diezel Weazel]

My question is , whats draining the battery ?
Surely if the lights are off its not using electricity.

Hi, Ya don't say what Truck ya have n does it have one or two batteries ??
Having two batteries one may be OK the other Iffy n the iffy battery will drag the other down. Ya need to get each battery tested with a Ammeter before n after starting ya Truck. If ya don't have one or not sure what to do any Motor shop will be able to perform this Test.
Hope this helps n good luck.

16+ Years of Surfs n 9 years on Spotless it ain't but Faultless to a "T" is my KZN 130 Yota !!

[Cranfield]

I have a KZN130 1993 reg SSRX 3.0 turbo diesel Surf.
It does have two batteries and I will get them checked.

[BillaBob]

Stereo Memory & Clock etc & Draining.

Just for your interest, the Stereo, & Clock etc drains minimal current, with healthy batteries you should be able to leave your truck for weeks & it should still start, & I have done with lots of additional accessories.Unless you have a fault, its beginning to sound like it is your batteries.
You can of course carry out a test to prove if you have excessive current being drawn, you would have to disconnect the main Accessory +12v from the battery ( not the starter feed) you then connect an ammeter between this wire and the battery with all the doors locked and shut and left as you would overnight .This will soon tell you if you are drawing current.