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Car battery draw current when engine is off


Joemit7850
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Neutral Newbie

I have this problem with my -99 Nissan Almera N15, it is draining my brand new battery overnight and i'm trying to figure out why...

I see a tutorial on YouTube how to measure how much the car is pulling from the battery when idle but when I connect my multimeter between the electric wire and battery terminal, I get 0 reading on the multimeter (I tried both, + and - cables/terminals).. Can this be because my multimeter is bad or am I doing something wrong? My multimeter is new also but it's not anything of good brand, the brand is the shop itself where I bought it... 

So why am I getting 0 reading when I add the multimeter to the circuit?

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29 minutes ago, Emil24 said:

I have this problem with my -99 Nissan Almera N15, it is draining my brand new battery overnight and i'm trying to figure out why...

I see a tutorial on YouTube how to measure how much the car is pulling from the battery when idle but when I connect my multimeter between the electric wire and battery terminal, I get 0 reading on the multimeter (I tried both, + and - cables/terminals).. Can this be because my multimeter is bad or am I doing something wrong? My multimeter is new also but it's not anything of good brand, the brand is the shop itself where I bought it... 

So why am I getting 0 reading when I add the multimeter to the circuit?

When you connect multimeter between wire and battery terminal, I assume you connect the meter in series. Then you need to set the multimeter to current setting and read current passing through the meter. If you have set to volt, then you'll get 0, bcuz the circuit is broken.

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Turbocharged

a gentle reminder

remember to switch your red probe from voltage/resistance/diode socket to one of the two sockets for current measurement

multimeter_1920.ashx?la=en&modified=2017

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The best way to check the amp drawn when the ignition key if off is to use a clamp on meter or amp meter plug directly to the suspected fuse route in the fuse box. Removing the live terminal at the battery and connecting the volt amp meter in series is the conventional way  but for some cars the dismantling of the terminal may erase all the memories in the " keep alive chip" Little knowledge is dangerous especially if you are trying to work on modern cars electric system.

Battery drain ( aka parasite drain ) need time and systematic checks with the right tools to get to the bottom of the problem.

Auto current tester.jpg

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Neutral Newbie

Yes, in series, my bad.

The multimeter is set correctly, black wire in COM and red in A and reading AMPS. Still I get nothing. Not even milliamps, just 0.00.

If I'm reading volts, I get around 12.80. And when engine is running, it's around 14.30 IIRC.

But what i've been wondering is that when I connect the multimeter in series with the wire and the battery, should there be electricity flowing in the car? What I mean is that if I leave say door open (so the interior light would turn on) or radio on, should they turn on?

(edit: I also tried to get readings on interior fuses when I connected the multimeter pins directly to a fuse and it showed me correctly like 0.30 when the interior light was on, but when everything was off, I got pretty much 0.00-0.01 on everything so there was no parasitic draw like shown in this YouTube tutorial: 

 

Maybe the problem is in the fuses found under the hood?

Edited by Emil24
New comment on the post when I was writing
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18 minutes ago, Emil24 said:

Yes, in series, my bad.

The multimeter is set correctly, black wire in COM and red in A and reading AMPS. Still I get nothing. Not even milliamps, just 0.00.

If I'm reading volts, I get around 12.80. And when engine is running, it's around 14.30 IIRC.

But what i've been wondering is that when I connect the multimeter in series with the wire and the battery, should there be electricity flowing in the car? What I mean is that if I leave say door open (so the interior light would turn on) or radio on, should they turn on?

Does your multimeter have a fuse ? It might have blown by a sudden surge in current. 

If your door is open, and you have the cabin light switch to "Door", it would try to turn on the lights, passing surge current through the multimeter.

If you want to check small leakage current, you should have everything turned off before you begin. Any ignition key also should also not be in the car.

For me, I would use a DC clamp meter.

Edited by Kb27
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Neutral Newbie

Sorry I couldnt reply because this site have max replies per day

The fuse should be fine because I am able to read battery voltages and it is giving me right numbers.. I get around 12.80V IIRC..

I indeed tried that, I left door open, disconnected minus cable and put multimeter between battery and the wire (AMPS, milliamps position)... Nothing... No reading, no light...

The battery is brand new so there should be no sulphate oxide coating... I have cleaned them anyway and I rubbed the multimeter pins pretty hard against the terminals but still I dont get any reading... I will try this with other car and other multimeter and see if it works there, maybe my multimeter is not sufficient enough

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On the multimeter, the fuse is solely to protect it during current reading (in series circuit).

Even with the fuse blown, you can still read voltage and resistance, bcuz these are parallel circuit readings.

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