Need Help -- 2008 Limited Battery Drain Problem

[enigma-2]

14.2 volts when running shows the charging system is working. Test battety voltage when the car is off (tests just the batterys voltage). Should be getting 12.2 to 12.6 volts. If it's less, assume the battery is not taking a charge.

 

Could be a bad new battery. New batteries need a full charge to srart off.  Freezing weather and a short drive home may not be sufficient to get an adequate charge.

 

In really cold weather, batteries not charged will freeze and short the plates together. And it's been really cold in certain parts of the US last week.

[Haz]

Welcome to the Forum, Skipper96.

 

Parasitic battery drain diagnostic reference...

 

Document download link> Parasitic Battery Drain Job Aid.pdf

 

Good luck!

 

Edited February 10, 2023 by Haz

[Brundenscoot73]

So I have a similar issue but I don’t think it’s battery related but sounds quite similar my battery is fine it’s new I even took it to auto zone to check and they told me it was 100 percent it isn’t the alternator because the battery is 100 percent so It seems to be may starter I replaced my starter and it worked great for a few month and then started doing the same thing again all my lights AC radio seats back hatch sun roof work but the car won’t turn it just clicks so I replaced my starter again last week even got new conectors for my battery works perfect for a few days no indicator of laboring to start and then this morning I get in my car and it won’t start I checked my fuses and nothing’s popped I really need help I’m from Houston  

[enigma-2]

It could be several different faults, but it really sounds like a parasitic battery drain.

  if so, these can be occurring sporadically and very difficult to find.

  One method (with the car off) is to clamp an  ammeter across the + battery lead and wait until it shows a heavy draw (It's normal to see a few millimeters to keep modules alive).

  Once the meter shows a draw occurring, you start pulling out each of the fuses on the power fuse panel, one at a time. Do this until the draw stops.

  Then determine if the draw stopped because you found the circuit or, the parasitic battery drain stopped. (If it stopped, replace the fuse and start with it when the draw starts again).

  You could wait 15-20 minutes between the parasitic battery drain starts again.

 

There are a lot of devices that could be causing a periodic drain. In the electric schematics, they are the ones that have two sources of power. Its the ones that have a hot at all times feed.

 

An example of a parasitic battery drain  could be the rear wiper. Suppose that the gear box got water in it and caused the gears to seize. (Wiper not seated).

  Even with the car off, the wiper checks to see if the blade is parked (through the "always hot" feed.) This occurs about every 15 minutes.

  If it isn't, it turns on the motor to park the blade. It stays on until the blade reports that its parked or it times out after a period of time.

  Problem is, this motor draws several amps and over a night the motor causes the battery to discharge (keeps pulling juice out and nothing going back in).

  I chose this as a motor starting current  draws several times its running current. Its called a locked rotor rating and if the rear wiper motor draws say 3.5 amps running at could draw 7+ amps starting. And if it's locked as in this example, it's always starting.

  So in this example, using a clamp ammeter, you'll only see the draw for about 30 seconds, once every 15 minutes. This is why some draws are so much of a pita to track down and why mechanics hate the process.