battery dead every 4 days

Alright, here is my deal.  I own a 2001 Nissan Maxima GXE, I live in a cold climate, Fargo, ND and we get anywhere from -40 below to 30 degrees F in the winter months.  My car battery goes dead every four days or so.  I really don't drive it that much.  Just checking if everything is normal.

Here is what I have:

-Aftermarket in-dash DVD player

-2 amps (sub & speakers)

-AstroStart 5204 remote start with alarm

-Bypasskit key immobilizer

-PAC SWI-X (steering wheel controls for my aftermarket deck)

-1 Year old Exide Orbital Battery (Gel type battery)

-130A Higher output alternator (stock is 110A)

Here is what I have done.

I found out how many amps (A) & (mA) my car is drawing  around 2 amps or 130ish (mA).  These results are when my car is UNLOCKED & unarmed.  This could be a factor.  I can disconnect my amp power wire and the (A) & (mA) are the same.

How I tested the amps using an Extech multi-meter was to hook the black tester lead to the (-) neg battery terminal (disconnected the (-) neg battery.  And then postive tester lead to the vehicle cable ground, set the multi to (A) & (mA).  Did I do it right?

Summer has never been an issue, but I guess I may have driven my car a lil more often during the summer months.  Heck, sometimes I don't even turn my stereo on in the winter.

My Questions are:

What is the voltage of a fully charged Gel battery, 12.6 volts?

Is weather a huge factor is killing batteries faster???  If I remember correct, I thought freezing AA batteries was good to prolonging there life, granted there not lead-acid or gel.

I bought a really nice battery charger and I may try charging the battery and see what the resulting voltage is.....comments?

We do rarely get really bad temps but its a factor of the north.

Alright, I did a test, switched the tester from going through battery ground to battery positive.  Same results.  Maybe its my tester, but when I have it set to (mA) it actually turns on the car hence I can see my factory security light blinking and set to (A) I see nothing. Hmmm?

Ok, both my audio amps are fine, not sucking any juice, so there out.  Then my car has two connectors, ones for the alternator & ones for everything car related.  I'm getting 150mA at just the car one.  I unhooked my Remote start and I was getting around a 150mA with it plugged in, now around 120mA with it not powered.

120 still sounds like a lot to, when I openned my doors, it went to around 200mA.  Is it worth investigating, pulling fuses & relay to go further?

I'm going to have NAPA check out my battery, still under warranty, charged it to 100%, 12.6ish, now its at 12.4 and the charger is saying its at around 70% power.

All car batteries tend to operate at ~12.5v - 12.6 is perfectly normal for a charged battery w/o the engine running.

Jeeze - if your battery keeps dying the battery is probably finsihed anyway.  car batteries really aren't mean't to be discharged - unless you are using a deep cyccle battery - discharging the thing once is a pretty good way to make sure it keeps happening every few days.  If you battery has died that many times, your total charging capacity is probably quite a bit lower than the specifications the battery was designed for - while the battery may read 12.6 at the poles, the battery is already dead and can't take any sort of load lest it give out almost immediately.

I'd replace it with something built withstand major, major abuse.  Have you looked at Optima's line of car batteries?

Based on that second test you did, it would seem that your car is working properly and the weather got to it. I just wanted to make sure that it wasn't anything electrical before assuming that the weather got to it. By this time I would agree with Sedate about getting a new battery.

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Brand name for the most part is not going to matter TOO much in this case. The key problem here is actually the temperature and not so much about the deep cycles (but not entirely ruled out) Since we are talking about sub-0 temperatures, you'll need a way to keep the battery above -22*F. Your typical battery whether it is gelled, spiral cored, or whatever will use the same basic principles in chemical reactions for the battery to work.

You were right in understanding that freezing batteries (such as AA or AAA) will extend their life, but that will also diminish their capacity. At -22*F, just about any battery will lost 50% of it's capacity. Even the optimas. Ideal ranging for batteries is between 32*F - 77*F. Above 77*F, the battery output is higher, but the life is shortened, and every 15*F above that the life is halfed even further. This basic system is fairly accurate for primary batteries, ie disposables, for secondary batteries (rechargable) the effects are a bit more aggressive but the results are still the same.

You said the temperatures drop down to -40*F... according to some calcualtions I had done, (well not me but someone who knows his stuff) Your capacity is approximately 25% of the battery's CA not CCA. So if your CA is say 600 amps, then the battery is at -40*F only 150 amps IF the battery is in good shape. Typical batteries if even 1 cell has dies would be reduced to about 120 amps, and more amperage is lost with every cell that dies, etc. Even if the battery is reading 12volts, the battery may have the electrical pressure behind it, but it won't have the current.

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Summary: Since you tested a low draw from the car itself, 150mA with the alarm active, then we know it isn't that. The other major affecting variable would be the weather vs chemicals. It's just too cold for a battery to maintain proper capacity unless you get a HC battery with sub-0 properties. Your other option would be to find a way to keep that battery temperature within typical chemical limits. (battery warmer for example)

Anything over 50mA is too much parasetic load.  A 'normal' OEM car will draw ~30mA with everything off.  Anything past 50mA and you're going to start having issues.

If you can figure out what the reserve capacity of the battery is we can figure out exactly how long the battery will last with a 130mA draw on it.  I would expect the answer to be around 4 days.

One last thing you may try is to hook the meter up the way you said you did first (- terminal to meter to negative cable), turn the meter on, and then wait 20 minutes.  It is possible that the BCM is staying awake and that is where the extra load is coming from.

One other point of concern is the remote start/alarm that is drawing 30mA.  I'm not sure what the normal current draw of a remote start/alarm is but that seems high.  I would expect it to be closer to 10-15mA. 

Don't worry about the current draw with the doors open, the dome light will throw off the reading.  It will also cause a sleeping BCM to wake up and become active, raising the current draw on the battery.

Today's update:

NAPA tested the battery yesterday and it still has well over 90% charge to it.

-15ish(mA) for my AstroStart

Its the last connector on the SECU (3rd), 2nd Grey one that is jumping it from 30 to 100mA.

I do have some cheap LED lights all over my car.

I have uploaded a 3 page PDF of my SECU connectors.  The connector in question that causes the 70(mA) surge starts at PIN 49 on Page 2/3.

http://www.adjenz.com/Upload/Print%20Screens/SECU.pdf   287KB's

The only obvious wire on the harness that is hooked up to anything (from the Remote start) is the Trunk Lid opener actuator, PIN 63

I have no idea on the ECU, clock, or anything else the car needs to power stock, but with everything disconnected I'm in the 30's (mA)

I have removed all LEDs in my car...from ignition ring to parking lights.  No go

I can remove the #13 fuse, I believe its called Room light or room something and it will go to the lower (mA).  All my lights have been removed, I dont recall messing with any interior lighting.  I did once blow #13 fuse.

The one thing I can test with my multimeter is seeing how many amps my car needs when its armed/locked.  My multi-meter wouldn't let me lock the car, just haven't enough juice.  And I can't lock my car corrected to the battery then switch it, because my alarm will go off.  I have tried putting the alarm in a valet mode, silenting the remote, everything can I still can't get it.

Maybe I have a bad SECU, argh, they're only $300!  :-(

I may see if I can find a better anameter around town or something that I can measure to see what the car reads when it is armed & locked.