Disco 2 Battery drain

[tom1979]

Over Christmas the disco has been parked up in the workshop pending a few little jobs. The ignition was off however I noticed a few weeks ago the battery was completely dead. It has got a new battery and I’m sure the battery is ok. When I plugged the charger in I could here the air compressor “pulsing” for a while, turned off the charger and it stopped, turned it back on and it pulsed a couple more time then stopped. No idea why or if it is related at all.

I did a test with the multimeter and it’s showing between 0.28A and 0.68A varying draw with the vehicle unlocked and the key out. I couldn’t test with it locked as it kept setting off the alarm.

Are there common things that can cause a draw like this?

 

[Dippypud]

Does your air suspension work as it should with no 'unwanted' lights showing ?

 

[tom1979]

Yes I recently had the 3 amigos and the previous owner had just pulled the leds out the dash! All sorted now, wondered if it’s related to the SVS modification ?

 

[Dippypud]

Yes I recently had the 3 amigos and the previous owner had just pulled the leds out the dash! All sorted now, wondered if it’s related to the SVS modification ?

Any other lights on the dash or instruments that don't light but should on 'bulb test' when the ignition is turned ?

 

[tom1979]

No all working as they should, no fault codes either.

 

[Dippypud]

I take it you still have air suspension and not a coil conversion ?

So you may have a little air leak ...

 

[tom1979]

I hadn’t thought of that would that cause problems even with the vehicle switched off?

It only did it the once. When the battery drained a second time it didn’t happen

 

[Dippypud]

Not usually, but never say never... a badly bodged radio fitment is more likely ...

Get a 10A multimeter disconnect the battery lead and route it through the meter, (don't switch the ignition on), and then pull out all the fuses or disconnect accessories one by one till the drain disappears, this will tell you what circuit the problem is with... or you can pull everything out to start with, and then reconnect circuits one by one and see when the drain is reconnected...

 

[tom1979]

Get a 10A multimeter disconnect the battery lead and route it through the meter, (don't switch the ignition on), and then pull out all the fuses or disconnect accessories one by one till the drain disappears, this will tell you what circuit the problem is with... or you can pull everything out to start with, and then reconnect circuits one by one and see when the drain is reconnected...

This was the test I did that gave me between 0.28A and 0.68A varying draw. I’ll try pulling he fuses one by one to see.
Many thanks!

 

[tom1979]

Today I have a draw of 0.04A, which after some googling and searching on here seems normal. I noticed that (with the key out of the ignition) if I open a door the draw shoots up to around 15 and then back down a bit, when the doors shut it goes down to only 0.68A and stays there, take the multimeter off and put it back on it goes back to 0.04. And that was with the interior lights forced off. I'll just have to run it and see how it goes!

 

[brian47]

Maybe @sierrafery can help here, but I believe that there is a "sleep" mode on the Disco 2, meaning that after a period of about half an hour the actual standby current eventually drops to about 30 or so milliamps.
Remember too that the security system must "stay awake" in order to maintain anti-intruder protection.

 

[tom1979]

Maybe @sierrafery can help here, but I believe that there is a "sleep" mode on the Disco 2, meaning that after a period of about half an hour the actual standby current eventually drops to about 30 or so milliamps.
Remember too that the security system must "stay awake" in order to maintain anti-intruder protection.

Thanks Brian, yes I did expect some draw from the alarm/security so thought 0.04 was ok, but maybe not 0.68. I don't fancy standing there for half an hour with a multimeter to see if the standby current drops!

 

[brian47]

Thanks Brian, yes I did expect some draw from the alarm/security so thought 0.04 was ok, but maybe not 0.68. I don't fancy standing there for half an hour with a multimeter to see if the standby current drops!

40 milliamps is probably about right but 680 mills is definitely too much. And there's no need to as you say "stand there for half an hour", just connect the multimeter and go in the house to the warm and make a cuppa, watch a half hour of daytime TV, have a snooze and go check it later in the afternoon.

 

[tom1979]

40 milliamps is probably about right but 680 mills is definitely too much. And there's no need to as you say "stand there for half an hour", just connect the multimeter and go in the house to the warm and make a cuppa, watch a half hour of daytime TV, have a snooze and go check it later in the afternoon.

I don't have one of those fancy ones with clips! Mine is a £15 special !

 

[brian47]

I don't have one of those fancy ones with clips! Mine is a £15 special !

Excuses! There's always an excuse

 

[gstuart]

found this sheet if it’s of any use

 

[tom1979]

found this sheet if it’s of any use

View attachment 138239

Many thanks! Never seen that before!

 

[gstuart]

Many thanks! Never seen that before!

good thats of some use to u , know the guys here are extremely knowledgeable, also had to go through everything when my main battery kept going flat

 

[The Mad Hat Man]

but not this?
https://www.landyzone.co.uk/land-rover/battery-drain-a-few-ideas.97870/

 

[tom1979]

but not this?
https://www.landyzone.co.uk/land-rover/battery-drain-a-few-ideas.97870/

Thanks I'll have a look. That didn't come up in the search!