Battery drain

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Langer

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Dunfermline, Scotland
Hi all I have a 99 dicovery 2 td5 which has developed a battery drain. I've tried disconnecting the battery and doing an amp drop and at first there was 2.36 ml a of a drain and then it dropped to 0.04 but still manages to drain over night I've tested this with all doors shut and bonnet switch closed. Any ideas or common faults that anyone can think of? cheers.
 
your figures dont make sense - I assume yu mean mAmp, not mLitres? - but if you only have a drain of 2.36mA or .04mA, your battery should last at least, say 800hours :confused:
simple maths - AH rating of battery, divided by current drain = hours it will last
 
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Hi all I have a 99 dicovery 2 td5 which has developed a battery drain. I've tried disconnecting the battery and doing an amp drop and at first there was 2.36 ml a of a drain and then it dropped to 0.04 but still manages to drain over night I've tested this with all doors shut and bonnet switch closed. Any ideas or common faults that anyone can think of? cheers.

leave the battery disconnected over night, connect it back in the morning and see if the car starts then..... just to make sure the battery doesnt "drain itself" by an internal defect. As mr. T.M.H.M. said those figures are irrelevant.... though usually when this kind of drain occures the guilty part is the alternator's diode pack
 
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Hi guys thanks it is mili amps too was just my way of writing it lol. I left the battery disconnected last night after trying to find the voltage drop so I will re connect this morning and see if it starts
 
wot Ah rated battery do you have?


lets assume its an 80Ah....

80/0.00236 = 33898Hours..... :rolleyes: - now unless I am mistaken, that equates to about 1400days or about 3.5 years - so something is wrong somewhere - you either have a much bigger drain, which you arent measuring, or your battery is as dead as a Dodo.
 
To avoid confusion I'd re-check the reading on the Amp scale and put up exactly what the meter says after 30 mins with keys out and all door shut and for good measure disconnect the bonnet switch.
 
Hi, Had a similar problem on 2002 disco V8, two things to check, 1) if you have towbar and 2 sockets then check power connection to aux plug, mine was situated above top right hand light cluster and was giving a power drain. 2) there was a 300ma power drain through slabs unit (common problem I believe on early slabs units). One way to rectify this is on one of the forums and involved working on the slabs unit in the footwell, as it is a bugger to get to I looked at the other end and worked in the fusebox by the battery. Current drain is via ABS fuse (fuse 11 I think) So basically have taken the ABS fuse out, taken the feed to the fuse and fed to a std LR relay in terminal via an inline fuse of same current rating, taken relay out back to other side of fuse. Power to relay taken from ign switch so when starting up there is power to slabs unit, when turned off relay cuts circuit and prevents current drain. If you have air susp as I do then I let the disco stabilise for a short time before switching off.

Hope this helps.
Regards

Baz
 
Rite connected battery this morning and it started so removed neg lead and connected multimeter one end to batt and one end to lead got setting to 20m on the amp section of the meter, got bonnet switch in closed position also removed interior light fuse so I could open the door or switch alarm on/off, it's measuring 0.31 ma with either the alarm on or off. Battery is a 70ah varta battery less than a year old i have no air suspension any more converted to springs (years ago).I've tried removing all the fuses one by one with no effect. Not sure what my readings should be but can only imagine that 0.31ma is to much hence my battery drain.
 
Rite found something else roughly once in every 20 times of locking/unlocking with the fob it drops to 0.01 mil amps unlocked and 0.04 locked but if I open the door it jumps back upto 0.31mil amps, the fuse is out of the interior lights whilst testing dunno if that makes any difference.
 
those figures are meaningless. unless you are getting figures around 300-800mA, you arent reading the drain. That in itself may point to the alternator. Check the battery voltage in the evening after a good charge, disconnect the alternator overnite, and then check the voltage in the morning.
 
Rite connected battery this morning and it started so removed neg lead and connected multimeter one end to batt and one end to lead got setting to 20m on the amp section of the meter, got bonnet switch in closed position also removed interior light fuse so I could open the door or switch alarm on/off, it's measuring 0.31 ma with either the alarm on or off. Battery is a 70ah varta battery less than a year old i have no air suspension any more converted to springs (years ago).I've tried removing all the fuses one by one with no effect. Not sure what my readings should be but can only imagine that 0.31ma is to much hence my battery drain.

Mmmmmmmmm
If your getting a 0.31 mA drain that is not excessive, anything below 50mA is not classed as excessive, what I'm not sure about is the setting you are using on your meter.
If your just measuring amps and not milli-amps it should read 0.05A (50mA) or less.
 
This has now been rectified. I got an auto electrician to check my drain out he found that the drain stopped when he took one of the fuses out under the bonnet, the fuse was one of the fuses for the abs which was a permanent live, taking it out put the abs light on. He got a wiring diagram but was unable to suss out why it was draining the battery so what we did was remove the fuse and find a ignition live, putting one live to the removed fuse and then another wire from the other side of the fuse into where the fuse would have gone so basically changing the permanent live to a ignition live. The jeep sat from thursday until tonight and started with no trouble whatsoever tonight.
 
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