Parasitic draw fun!

[Biggins240sx]

Alright so I've had the problem for awhile now. Never did really fix it. I let it sit over night and my battery is almost dead. Engine cranks real slow until it can't. Now i got the car in June 2009 off my dad, we traded vehicles a truck for a car. My dad took it to Nissan for this problem: 5 batteries and 4 altenators later, they still could not find the problem. So I just dealt with it. Then one day I found out the light in my back hatch never went off, so i checked the switch and found out that when I close the hatch it never pushes the spring down to turn the light off. So I unplugged it. Fixed the draw for a bit. Then the car would die in Eight hours. I put another altenator in it as well on nissan's dime. Still under their warranty at the time. And had to put another battery in after so many constant drains. So 6 batteries now and 5 altenators. And now again its draining.

So here Im going to start to look into this problem again. I have audio equipment in my car so I started by testing it first. Charged my battery up, disconnected audio and let sit over night. Battery Drained. So I can rule out my subs, thank god! Now its time to find the actual draw. Now every time I have done this, I have found that the altenator seems to be causing the draw, so Im going to test it again. And why do I say that , well I used to work for honda and we worked next door to Nissan. And one of the techs used to work at nissan and remembered my car. He helped me find it. But its been awhile since then. So now Im going to restart this beautiful journey of looking for my draw. Yippee me.

*UPDATE*
The draw only drained my battery to 11.6 volts. But not enough to start my car up. So I tested for any amps and found none. No draw. Kinda confusing. But I have a friend on their way to jump my car off so i can let it charge, and retest this draw. And while im at it, he needs me to look at his Altima.

[PapaSmurf2k3]

Unfortunately I have the same problem with my 240... and it seems to come and go. My battery isn't the greatest, but I have the opportunity to put the battery on one of those battery maintainer things every night.

The only thing I KNOW is draining my battery is my ipod. Its constantly charging in there, but damn, there's no way that is killing the battery in a night or 2.

[Biggins240sx]

I have my own battery maintenance charger. But it's at my friend's dad's house. He is using it. He also is like my tool supply. When I don't have it. He does!

[CrabFishes]

Step 1, install inline amp meter.
Step 2, start pulling fuses till it reads 0(Or very very close <40milliamps)
Step 3, trace what fuses caused it and fix whatever problems if any on that circuit.

[compactfean]

Step 1, install inline amp meter.
Step 2, start pulling fuses till it reads 0(Or very very close <40milliamps)
Step 3, trace what fuses caused it and fix whatever problems if any on that circuit.

I second this test procedure. Two most common draws I've found is flasher shorting and blower motor resisters.
Good luck and keep us posted

[ShouldaHadaV8]

And I thought I was the only one who couldn't figure it out...lols
The last three owners of my 240sx couldn't figure it out either.

[Biggins240sx]

alright heres the deal. Put an amp meter on it. Fully charged battery. Shows no mA at all. shows 0. But still drains battery. Can't work on it either. Leaving tonight from fl and going to NC for spur of the moment trip. Friends said lets go b4 our boy goes to jail, so I was like ok. 11 hour trip and coming back sunday. FUN FUN!

[compactfean]

Dont know if this will help but I've always just disconnected negative cable and put a test light in between terminal and cable. Then start pulling fuses to see which circuit dim the test light. When pulled. Good luck ...have fun

[CrabFishes]

Op how are you hooking up the inline amp meter? And what kind? If its reading 0mA then its not a parasitic draw. Do you have an inductive amp meter? If so hook up the inductive, and turn your stereo to max and drive the piss out of it for a while, take the readings and compare to your alternator spec. Whats the standing voltage during idle? Not to sound like an a** but most of the time when you read 0 mA that means you have the meter hooked up wrong. Or the meter is broken. You normally would see some form of a draw at all times, usually from security modules, clocks, ECU whatever.

[slikklogic]

check alternator diode

[OutToWinPAHC]

Parasitic battery loss is the technical term for this problem. It is caused by two root factors.

A – A circuit or device in the car that stays on drawing current. All cars have circuits that do this such as the ECU, clock, and headunit memory. Those items are not issues usually, unless something breaks down in these devices causing them to draw more current. But if you have added new devices like amps, caps, engine electronics, they could be wired incorrectly causing them to stay on all the time. The other thing that can cause this to happen a nick in a harness shorting to ground. It may not be a hard short due to a painted surface, but if there is a current loss you will drain the battery.

B – The other thing that causes this… A leaking battery. When a battery dips or leaks it leaves a trail of electrolyte down the side of the battery. The chassis is grounded so if the battery is leaking a little (like a single drip that runs down the side of the battery) it will make a trace to ground. Kind of like a tiny solder trace on a board. Current flows down this trace to ground causing a small but stead discharge of current. If you battery is leaking replace it. If you have wet mark around the terminals or green fuzzy looking stuff known as copper sulfate on the terminal replace the battery and cable.

[OutToWinPAHC]

As stated before, use an inline current meter, pull a fuse with the car off, ignition off, and see whats pulling current. the meter on DC current completes the circuit letting current flow through it. Also clean the battery and battery tray.

[Biggins240sx]

Alright I'm back from Jacksonville, NC. Haven't tested it yet again but started looking through wires. Battery is fine, no leaks but did find a wire cut from the ECM. Pin number 32, which goes to the tach. I'm going to seal that up later. Then retest.

And Happy New Year!