300tdi battery going flat

I have a massive 800CCA battery on the disco, it goes flat over 3 weeks any top tips to save me hours of looking for whats draining it?

Fit an isolator so you can turn it off when not in use

have u had the alternator checked out first , so at least u know that's ok

measure the volts with the disco off and then running

know when i've had battery drain , got a multimeter , sat there with a cuppa and tested the back of the fuses one by one

but of course waited till its gone to sleep to get an accurate reading

don't know if this is any use to u

winchman said:

I have a massive 800CCA battery on the disco, it goes flat over 3 weeks any top tips to save me hours of looking for whats draining it?

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NO, suck it up and do a battery drain test....... Should not take that long anyway.

@gstuart has given some good info above.....


Cheers

Very little drain on a D1 - so... I suspect your battery may be at the end of its life - or the alternator needs some love..... easy to do the tests, and easy to test the battery too... you might find halfrauds will test it for nothing

Thanks both batteries test fine so time to have a look once the wind stops

Had a problem with starting during the recent cold spell. The problem proved to be a dying alternator which eventually gave up the ghost. Had the existing alternator removed, reconditioned and refitted at a total cost of two hundred euro.

The auto electrician also checked the battery which proved to be low on water. Everything now appears to be working well, battery charging and holding the charge, despite the fact that it has only had a few short journeys to boost the charge.

neilly said:

NO, suck it up and do a battery drain test....... Should not take that long anyway.

@gstuart has given some good info above.....


Cheers

Click to expand...

do try and help where i can, lol

neilly said:

NO, suck it up and do a battery drain test....... Should not take that long anyway.

@gstuart has given some good info above.....


Cheers

Click to expand...

But no good to an owner of a D1

winchman said:

I have a massive 800CCA battery on the disco, it goes flat over 3 weeks any top tips to save me hours of looking for whats draining it?

Click to expand...

Is not the CCA that's important with battery standby but the the amphour (Ah) of the battery.
I'm on my 3rd battery and I might just be lucky if the engine started after three weeks with any of them, But noway will start if l unlocked/locked a few times over that time.
When you say "flat" do you mean zero volts in the batter or voltage has dropped to around 10 therefore the engine won't start?
Lots of tips on battery drain if you search google but that is for a battery that's fails overnight, not three weeks.

While @discool is generally correct that the table provided by @gstuart isn't of much use to D1 owners, but as an average figure it does give a sort of cut-off figure, a place to start from. A Disco 2 after letting everything shut down draws 20mA. That's 20/1000 of an ampere. In other words, not much at all.
Not knowing the size in Ah of the battery which is going "flat" does make understanding the problem fully a bit more difficult, but to give you some ideas, a 75Ah battery should be able to supply 1 amp for a period of 75 hours, in basic terms.
You say that "both batteries test fine", it would be interesting to know what was used to come to that impression, a voltmeter or a load or drop tester?