dirtfan50

I have a 1996 LS400 with battery drain issues.
Replace the alternator 6 months ago.
Battery replaced April of 16.
When i have the car running the alternator is at 14.2 amps.
Turning the headlights on along the the heater on high it drops to 12.9 the rapidly back to 14.2 amps..
I turn the car off the battery amps alone are 12.9.
When i walk away for 30 minuets or so its dropping down to 12.2 amps...
I have locked the hood latch ** its electric but no under hood lamp } all doors closed while im doing this.
I can leave it setting overnight and the battery is to low to start it with out jumping it again.
What could anyone suggest as far as test further to see what is drawing the battery down...

Thank you for any suggestions..

dicer

I think you have AMPS and VOLTS switched. How are you checking for amps? To do so you literally disconnect one cable off the battery and then put the amp meter in series that is one wire from the amp meter goes to the battery and the other wire goes to the cable clamp. And if you did that with a normal DMM there is no way you will start the car. The wires are just plane too small to support the cranking amps. So I don't think you were checking amps at all.

dirtfan50

I have the meter on 20 dcv on my tester.
the reading I was taking it from was just putting the red probe to pos and black to negative.

checked it about 2 hrs later it went from 12.6 down to 12.4 and wouldn't crank.

dirtfan50

By doing it this way I thought I would see what the output of the alternator while running then shutting off I could see the charge on my battery.

dicer

You were then checking the VOLTS not the amps. Your readings above look fairly normal. And that is how I figured it was volts. The 20DCV means that max range in that position is 20 Direct Current Volts, the other 20 option would be ACV meaning Alternating Current Volts. The word current meaning what is happening to the flow of electricity not what you are measuring. The meter is connected in parallel to check for Volts, and in series to check the current flow. They do make inductive amp meters that will work for both ac and dc amps and that would be the best way to check for the amps or current. And I know for sure you very likely will not show 12. something amps with nothing turned on. I a light is still on then maybe 3 or so.

dirtfan50

Thank you for your information.
im just baffled at what's doing this to the car.
my guess the alternator and battery is good.
just can't trace what's pulling the battery down while just sitting and not running .
everythings turned off.

dirtfan50

dicer thank you for correcting me..
i never realized i was saying amps till you brought it to my attention..
volts is what was meant.. i guess being so frustrated trying to figure this out is taking its toll on me..

djamps

What I usually do (initially, at least) in these situations is pull one fuse at a time, and probe the fuse terminals with a DC Amp meter. Make sure the meter is fused internally at least, and in DC 10 Amps mode which usually has a separate plug for this, if you're unsure how to use a meter consult with someone or online first. Do this one at a time for each fuse in each panel until you find the current draw.

oldskewel

iTrader: (1)

If it is easy to swap batteries between this and another of your cars, or a spare, the results of that simple test would tell you whether or not there's a problem with your battery. Regardless of age, batteries sometimes fail internally.

dirtfan50

Battery has tested good?

oldskewel

iTrader: (1)

Probably means it shows 12+V and a certain number of CCA, if they tested that.
Still, it may be the cause of your problem. I doubt anyone will test for an internal parasitic drain.
If it's not easy to swap, then I'd follow the fuse pulling approach. But if you have a second car or a spare battery you can swap, that is pretty easy to do, and would be an important experimental result for your issue.

dirtfan50

I have removed 2 fuses
the phone and the alarm.
i keep checking the volts on the battery and it hasn't dropped at all like previous checks ... you could almost watch it drain.
i need to dig further tho on the fuses. The alarm fuse has the remote key fob and door locks not working.
thank you for any and all your input helping me.