So i know that the antenna for my radio is broke and it makes a noise (trying to go down) when i turn of the car. But after thats done i can still here something making a **whiring** sound in the back of the car. Not sure what else it could be but the fuel pump. I've come out even 2hrs after the car has been off and can hear something run for about 10-20seconds.

So if i let my car sit for about 2-3 days the battery is dead or near dead. Now i've started to pull my fuel pump fuse and i think it helps. I've made sure all my lights, heater fan, dome lights, cigarette lighter, radio. are all off. Not sure what else would run and kill my battery. Any Ideas

 

well, as far as I know, the fuel pump does (or should) not get constant power. It should be regulated thru a relay.

have you tried unplugging the antenna power, to rule it out as a possible source? it always gets power, and has a trigger wire from the stereo.

 

Measure the leak current at battery: neg pole connector off, bridge this gap with dmm (selector & wire at amps scale).

If the reading is over 0.05A - theres a problem. Start unplug/reinsert fuse -game until it has been found...

 

so put a multimeter on the positive side and then ground it to the block with the negative battery cable off? then if the draw is over .05amps start pulling fuses till it stops?

Sorry not all that good with car electronics.

 

There was a recent thread about that noise. Cant find it or recall what it was. Evap system?

But that shouldnt kill your battery.

What Wiking is saying is put the meter in series with the neg cable. Basically the negative wire will go into one side of the meter and the other side of the meter to the battery negative post. Make sure you set up your meter to read amps. Dont turn anything on as most meters arent rated to handle too many amps. And keep the door closed. Just pull fuses until you see a drop in current. That will be the component with the drain.

 

Ahhh much clearer... so i'll hook it up place my meter resting on my windshield and sit in my car if there is a draw and start pulling fuses. I'll try some "rearend noise" ( no not that kind ) searches and see what i come up with. Thanks

 

Yes.

Think water in a tank, pipe to the cattle drink drum. If the piping has a big leak, your tank = battery will run dry overnight...

Now some leak is envitable and accepted. Here you use a gauge to measure how much that leak is: you disconnect the pipe at source, let water flow
>-through->
your measurin device = What goes in, the same flow goes out towards the leak / cattle drum...

As said above, your digital multimeter is in series and measures all the current going through. Pull/Insert all fuses while checking the flow through. Acceptable maximum leak current is 0.05A when all fuses connected (yes, doors closed, radio etc powered OFF). (Disconnect alternator wires if necessary).

Observe the multimeter probe connectors: typically theres a different connection for 10-20A measurement. And later, if u forget that and try to measure voltage with that setting, dmm is fried. I happen to remember the stink...

 

found the thread.... <---


seems like a bad relay somewhere.....

Now how do i fix this

 

Relays, troubleshooting via swapping: all Nissan relays are color coded. Each color represents one type of relay /pin settings. Find out where they lurk and swap and figure out if smtg changed or not.

While there, use/spray contact grease on each and every pin.
see http://www.cardomain.com/ride/748507/14

 

wrong way

Quote:
Originally Posted by braxsusriely
... Any Ideas

Measure the leak current at battery: neg pole connector off, bridge this gap with dmm (selector & wire at amps scale).

If the reading is over 0.05A - theres a problem. Start unplug/reinsert fuse -game until it has been found...

Remove the negative battery clamp/connector and measure between the negative post (battery) and the negative clamp current draw. Start pulling fuses to find circuit with current draw!