electrical drain

[Stagdad]

Went to start the stag on Saturday and it was quite flat but just turned over enough to fire up .went for a run and 14 volts wereindicated when i got back home turned it of and it restarted with lots of power in the battery.Sunday morning same thing happened so i gave it a run and then disconnected the battery .Tried it tonight after reconnecting and it was fine so i'm thinking it has developed a short some where .

So my question is how do i use a multimeter to measure battery drain whilst i pull out fuses and the like to try and isolate the problem.

I hate auto electrics :X:X:X

Cheers Steve


PS I have a clock which will draw some current do i need to disconnect that whilst testing?

[mad cyclist]

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have you got a charger with a battery condition light, also if its not sealed is you acid up over the cells?

I have pulled out a bit of hair in the past on electical front, now i go to work and sell sparky problems to someone else!!

[european voyager]

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Just a thought stag dad , Check the boot light is switching off when the boot is shut , you dont need to hide in it feel it on it will be hot !

Also worth checking the glove box light goes off.

[KOY 23]

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Hello Steve.

If your meter has a 10Amp range connect the meter in series between the battery and earth lead. Make sure you use the correct sockets on the meter and everything in the car is off. See what the current drawn is. If about 10mA that would be the alarm and clock. If 500mA boot light. More than that, you need to pull fuses out to see which circuit has the problem. If all fuses out and still significant current drawn, could be an alternator diode.
Let us know what you get.

Good luck

John.

[GDPR]

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I would pull the alternator plug first John - experience of sparking in a pro capacity for some years has shown me that the Lucas alternator is the devil's own spawn, and a diode will go leaky very easily..............being that it is so easy to disconnect it's a no-brainer to go there first..

If you don't have a ammeter range on your meter, and you don't have an alarm, you could if your meter will co-operate, do the volt-drop test..... disconnect the earth cable from the battery, and connect the positive lead to the earth cable and the negative lead to the battery post (this is best done with an old fashioned meter with a needle rather than digital)..... volt reading of 12, something is on and drawing juice. pull the clock power and see if you have 12 still.....if so move on to the fuses -you want ideally zero when you find what's sucking the power (always disconnect the alternator terminal for this test as there is always a small volt-drop through it that will mislead you)

Good luck

Russ

[Stagdad]

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Thanks guys, Excellent stuff

Should just add that i already have a fault in that the Brown wire ( ignition control) and the purple wire (battery control) some times become one circuitso i have put the purple onto the same fuse as the brown and now all the interior lights are only on with the ignition ,other wise the ignition was coming on at random some times ,so any way there is no chance of the interior or boot lights staying on.

Did i mention i hate Auto electrics

Needless to say a complete sorting of the wiring is on my to do list.

Cheers Steve

[Stagdad]

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Just bought a digital multimeter with 10 amps so should be able to start investigating soon.

Cheers Steve