My son's minivan (work) has had a recent issue of battery drain. Figured the battery was bad so it's owner replaced the aging battery.

Fast forward to the next weekend and it's dead. Jumped it and OK, I disconnected the battery, but when I did, it sparked quite heavily, It is a service van, with equipment. Everyone was turned off but yet a healthy spark. Could the alternator cause a parasitic draw? I know they have an internal regulator.

I'm attempting to locate one on my '89 Diplomat Police car. I pulled every fuse and still had a 60 Milliamp draw which is high for an older car. I was about to test with alternator disconnected, but needed to change batteries in my voltmeter, and when I opened battery compartment they had leaked out and destroyed it. So that's my next thing. Another voltmeter should arrive any day now. Lots of suggestions here;

https://board.moparts.org/ubbthread...tic-draw-or-bad-battery.html#Post2864873

Be sure to ck glove box and console light if equipped .

Every time I’ve found an alternator causing a draw it’ll be very warm while setting.
Doug.

Will do although I think that was covered.

How might I check this with a meter. I'm totally ignorant of electrical testing. I do know it makes quite a spark when it disconnects

Disconnect negative battery cable, and you want the meter to have one contact on the negative cable and one on the negative post. Doesn't matter which you use from the voltmeter on which because you are just looking for an absolute value so ignore the negative or positive reading on meter. On older vehicle without a bunch of electronics, should be a reading of less than 50 milliamps. Mine is reading 60Ma and killing my battery in just about ten days of sitting. The van being a '13 may read more in the range of 60-80 milliamps, and be considered normal draw.

Basically, the meter is going to be a link from negative cable to negative post, using meter contacts. I believe the knob setting on your meter should be mA, or at least on most meters.

Easy way.
Pull the van someplace dark. get inside , make sure key is off and all doors are shut and wait till time delay times out ( about 30 seconds ) The key in ignition cylinder light will go dark when it does

Once happens open the console lid ever so slightly and look for lighting inside, OK?
Look for light illuminating from under the dash near the glove box ,,,this might require getting your head under the dash. ( hopefully you're young enough to get back out of said position )

PS, if it has an underhood light . They are notorious to fail causing the light to stay on , trust me

it should have a IOD rely/fuse,(ignition off draw),pull that and see if it goes away

Thats right as I found most newer Mopars read from 10 to about 30 mili-amps. I was told 50 mil-amps even for the new cars is limit and I only found some conversion vans reading about 40 to 50 mili-amps. I always like to use my fluke meter as its digital readout is very accurate. Ron

I am waiting on my new voltmeter to arrive. As I mention the old one was ruined by batteries leaking out. But I’ve had the alternator disconnected for three days and I connected the battery charger this morning and the battery was still at 100%. This makes me almost 100% certain it was my alternator. Every time before that I’ve let it sit for three days it would charge at 2amps for at least 90 minutes. This is best case scenario for me too because I have an extra alternator pulled from another police car i used to have. And having already pulled every single fuse with no change in the draw I was getting frustrated. Oddly enough my alternator was never warm though when the car was sitting.

Magnumguy here’s what my voltmeter look like with the dial set and proper ports for the leads when testing in Milliamps.

To verify your thoughts you could disconnect the wires atteh alternator (tape off the fat one) and reconnect he battery and let it sit. then see if it drains.

Why let it sit? Just put the ammeter in the circuit and check for a draw...

Because he's waiting on his meter to arrive, so he can't use that.

I just had this same issue with my 2011 Ram 1500. When you park it listen by the fuel tank. Fuel pump may be running. There is no relay in the system. They expect you to replace the entire TIPM. (Fuse box)
I found a company called vertical visions that makes a solution. Cost me about 100 maybe 150 and took 20 minutes to install.

https://www.verticalvisions.com/

When it shows up, strip the alternator down and see what's up. Not that hard to rebuild.