I have a 1999 F250SD with the 5.4 and am experiencing parasitic draw. Battery and alternator are fine, but if I charge the battery, it winds up dead after a few weeks. Admittedly it
s not used a lot, and when it is, just for short runs (less than 5 minutes).

I need to hook a higher reading meter to it. Right now, my little meter pins the gauge hard at .35 amps.

Pulling fuses is my next step, but I need to see if the meter shows a drop which means I need it to read in the scale, not pinned.

In the meantime are there any known, or common things that can cause this?

 

Normal draw is up to 80 MA with all the electronic crap on todays vehicles. Your .35 is 350 milliamps. Yes, start pulling fuses one by one. I cant say ford has a issue with body control modules however some like Jeep is notorious for the BCM staying "awake" and killing a battery withing a week. I can say one the CD player in my jeep thought a CD was still in and the drive stayed on even with the key off. It pulled power from the yellow memory lead that kept the CD's place and clock going. Id also say that 5 mins a week is not helping. A family member only drove her car to the grocery store once a week which was about 5 mins away. She kept complaning about a dead battery. It just dont get charged enough with those short drives. Might check out the "Innova 3721 battery monitor" I have one and its helpful as you can see it while pulling fuses or just monitoring things.

 

According to my Owner's Manual, there are two fuse/relay panels. One is under the hood and they call it the Power Distribution Box. The other is behind the access panel near my knees. They call it the Passenger Compartment Fuse Panel. According to my Service Manual (Chilton and in yellowed newsprint no less!) the one under the hood is the Battery Junction Box and the one inside is called the Central Junction Box.

There are two fuses, both located in the box under the hood, that will eliminate the current drain. One is Fuse 29, and that makes sense as it's connected to the radio memory and I think a few other things. So I left it out for further testing.

The other fuse is also in the box under the hood and is Number 22 and is a 50Amp fuse.

My Owner's Manual says it's for the Instrument Panel Junction Box. None of my schematic diagrams show this Fuse, nor to they show anything called the Instrument Panel Junction Box. So I can't trace the wire further.

Does anybody have further information on this fuse and where it connects to? Factory wiring diagrams ought to show it... I would hope.....

 

I found a thread with the same question as I have. The 50 Amp fuse turns out to be the under-hood feed for the second fuse box under the dash.

He was advised that #22 is a 50amp feeding others in the Central Junction Box #13 , #15 , #1 , #12 , #2 , #3 , #4 , #14.

So basically pull each one until the parasitic draw drops off.

#14 is the interior lamp relay and ACC delay relay
#4 is a bunch of map lights,glove box light, hood light , etc
#3 is OBDII connector and Cig plug
#2 Instrument cluster, PCM, Keep Alive Memory
#12 is the horn relay
#1 is the flasher relay
#15 is a GEM PCM ABS power wire
#13 is several brake switch circuits

I find removing numbers 2 and 15 (both at the same time) drastically reduced the drain. Just one or the other did not.

Now this thread was started by a fellow who thought he had parasitic drain. He measured about 1.5 Amps, which is what I now measure with my better ammeter. However he finally had thoughts about his alternator as it got slightly warm after the truck was turned off.

I have the same drain, but with the alternator disconnected. So more investigation, but at least I have some leads to follow now.

On the other hand, it's been very cold, the truck has had numerous very short runs and the battery is the bottom of the line CarQuest; DieHard Silver @ 650 CCA. Maybe I'm chasing the wind....

 

Fixed, but not sure how. This appears to me to be normal:

1/ Pull fuse 14 in under-dash fuse panel to disconnect dome light. Otherwise hard to get readings below.
2/ Disconnect negative battery cable.
3/ Connect ammeter between neg. battery cable and neg. battery terminal.
4/ Ammeter goes to 1.5 amps for a few seconds, then drops to 0.122 amps.
5/ After 45 minutes or so the drain drops to between 0.05 and 0.070 amps (clamp on DC ammeter fluctuates a bit that low).

Drain goes to zero if both Fuses 2 and 15 are pulled, but it's the normal amount... due to radio and PCM memory currents. Also goes to zero if Fuse 22 Under-hood fuse panel.

So... my problem is gone. I suspect is a relay was sticking and as so many of them are identical, I didn't necessarily put them all back in their original location. Or maybe just infrequent use and short trips (as less than 200 yards)???

I still havn't put the dome light fuse back in, but I never did have a problem with it. I'll install it this week and see if any problems come up. Cargo light was in good shape... no water ingress or corrosion.

 

Take your truck out and drive it 20-30 miles once or twice a month. That will help not only keep your battery charged, but will held keep the oil from sludging. And change the oil once a year, no matter how few miles you put on it.

 

Little update. Turns out the panel light dimmer was set to the ON detent. Seems to take 15 minutes or so for the dome lights to shut off after closing the door.. If it's not in that position, the dome light shuts off much sooner after the door is closed (less than a minute). That combined with multiple short trips (100 yards or so) seems to cause the battery to die. I feel a little foolish now......