Any Nissan Techs Here? - Parasitic Current Draw

[SuperBusa]

This is a 2004 Altima 3.5L SE. Car still has the original OEM battery. Car sat for about 3-1/2 days, and went to start it and the battery would barely turn over the engine. After 2 or 3 engine rotations it died. Measured the battery voltage and it was ~ 10.6 volts ... dead. First time this has ever happened, and I've let it sit much longer than 3 or 4 days before.

Charged the battery and got the car started. Measured the charging voltage across the battery and it was ~ 14.3 volts @ idle ... normal.

Drove the car for the next 2 or 3 days and the battery seems to start the car fine.

Did a parasitic current draw measurement with an accurate Fluke DVM while the car was off, key out and locked. Current draw was a stable 70 mA.

Does anyone know if 70 mA is normal for this Nissan Altima with the car off, key out and locked up? Seems a little high, but maybe per spec (which I don't know - not in manual). If 70 mA is normal, then I guess it's time for a new battery. Should get one anyway based on the fact the original is ~ 7 years old.

 

[Nick R]

7 years sounds about the right time for a battery to go. The original Motorcraft battery on the expy lasted 6 years, had to replace it last winter.

 

[SuperBusa]

Originally Posted By: rudolphna
7 years sounds about the right time for a battery to go. The original Motorcraft battery on the expy lasted 6 years, had to replace it last winter.


I agree it's time for a new battery ... I have a new one sitting in the garage waiting to go in. But I wanted to make sure the car isn't drawing too much current on the battery when it's shut off. If so, then it's more than an old battery problem.

 

[JHZR2]

10.6v sounds like an internal short to me. I'd replace to be safe...

 

[mechanicx]

I don't know the Nissan spec but 35-50 MA is typical spec iirc for GM. but from the times I've measured current draw 70 MA isn't too uncommon and the batery would not drain. I think your current draw is acceptable and should not drain your battery.

 

[Scott_Tucker]

To accurately test it, you need to have a known good battery anyway so you might as well install it and recheck the current draw. Normally, anything less than 50 mA is perfectly fine. I think 70mA should be OK, I don't know what the spec is. At that draw the battery voltage probably wouldn't go below 12.0 volts for a week.

 

[SuperBusa]

Here's an update that some may find interesting and something to remember when doing a current draw test on a newer (computerized) car.

I recall doing a similar parasitic current draw test on another car and discovered the computers need some time to "go to sleep". So on my Altima I left the current draw test setup intact for an hour and did another check and the current draw was down to 15~17 mA.

Apparently, it takes some time for the "sleep level" of the electronics to kick in on the newer cars. So, based on that I have no worries that there is an electrical issue and it's just a battery going south.

Got the new battery installed and all went perfectly ... great fit and I had a change to clean everything up while at it. Checked the charging voltage with the new battery installed and it was 14.3 volts ... all normal.

 

[mrsilv04]

Neighbor had to replace the battery in his wife's 2005 Altima V6 a few months ago for the same thing. It sat a few days and wouldn't start.

 

[SuperBusa]

Originally Posted By: mrsilv04
Neighbor had to replace the battery in his wife's 2005 Altima V6 a few months ago for the same thing. It sat a few days and wouldn't start.


Probably just the battery getting weak like mine did. The OEM battery in my V6 was only rated at 550 CCA, which is small compared to some batteries its size.

In my situation I think the battery might have had an intermittent internal short, or else maybe the computers didn't go to sleep like they were supposed to and the parasitic current draw was too high for the 3-1/2 days it sat.

All the testing I did on my Altima says the charging system is OK and the parasitic current draw is 15~17 mA which is about as low as it gets for a computerized car.

 

[mechtech2]

It's battery time.
But to test for a high draw, put your ammeter in series with a battery cable and pull fuses to see which circuit it is on.
70MA is not outrageous.

 

[SuperBusa]

Originally Posted By: mechtech2
It's battery time.
But to test for a high draw, put your ammeter in series with a battery cable and pull fuses to see which circuit it is on.
70MA is not outrageous.


Yes, that's the only way you can get a parasitic current measurement.

You missed my update. Yes, I agree 70 mA seemed a little high to me because my other car only draws 20 mA.

I let the Altima sit for 45 min ~ 1 hr in the test config and checked it again and the current draw went from 70 mA to 15 mA. Apparently, it takes some time for the computers to fully go into "sleep mode". This is not the first time I've seen this ... and that's why I let it sit a bit to see if it would go down.

So, for anyone who's doing a parasitic current draw test on any modern car ... be sure to let it sit for an hour before concluding what the current draw really is.

New battery was put in last night ... all seems well.

 

[Vikas]

So, for anyone who's doing a parasitic current draw test on any modern car ... be sure to let it sit for an hour before concluding what the current draw really is.

I will go one step further; replace the battery first if it has more than year on it before even hooking up the multimeter. If you have purchased one from Walmart or Costco, get a new one first and if that one starts dying on you, then take out the multimeter.

- Vikas

 

[CharBaby]

Originally Posted By: SuperBusa
This is a 2004 Altima 3.5L SE. Car still has the original OEM battery. Car sat for about 3-1/2 days, and went to start it and the battery would barely turn over the engine. After 2 or 3 engine rotations it died. Measured the battery voltage and it was ~ 10.6 volts ... dead. First time this has ever happened, and I've let it sit much longer than 3 or 4 days before.

Charged the battery and got the car started. Measured the charging voltage across the battery and it was ~ 14.3 volts @ idle ... normal.

Drove the car for the next 2 or 3 days and the battery seems to start the car fine.

Did a parasitic current draw measurement with an accurate Fluke DVM while the car was off, key out and locked. Current draw was a stable 70 mA.

Does anyone know if 70 mA is normal for this Nissan Altima with the car off, key out and locked up? Seems a little high, but maybe per spec (which I don't know - not in manual). If 70 mA is normal, then I guess it's time for a new battery. Should get one anyway based on the fact the original is ~ 7 years old.


SuperBusa
I just replace the original OEM battery in my 04 Altima 2.5S. It did just the same thing as yours...Just recently(Sun,1-31-10), went to start the car and turned slowly and died. Read the voltage and it was about 11. Hit the key and the voltage dropped right down. Was going to W*M anyway so I pulled out the battery and took it with me. Drove my wifes car. Haven't had a problem since. Got the higher CA/CCA of the two available EverStart MAXX. $81.00 w/tax

 

[SuperBusa]

Originally Posted By: Char Baby

SuperBusa
I just replace the original OEM battery in my 04 Altima 2.5S. It did just the same thing as yours...Just recently(Sun,1-31-10), went to start the car and turned slowly and died. Read the voltage and it was about 11. Hit the key and the voltage dropped right down. Was going to W*M anyway so I pulled out the battery and took it with me. Drove my wifes car. Haven't had a problem since. Got the higher CA/CCA of the two available EverStart MAXX. $81.00 w/tax


I'm happy with the EverStart-MAXX I put in the Altima. Has 700 CCA and I can really tell the new battery cranks the engine over much faster than the old weak OEM battery ever did. It also fit very well in the car, which was a plus for me. I hate batteries that just don't quite fit or mount perfectly in the car. I'm betting your 2.5L Altima probably has the same "24F group size" as my 3.5L V6.