So I have a bad amp draw on my '01 F350 with the 7.3. I've traced it to the #15 fuse under the dash. My meter drops from 167 miliamps to 60 when I pull it. It's a 5amp, book says "Switch (Logic): Generic Electronic Module (GEM), Powertrain Control Module (PCM), Four Wheel Anti-lock Brake System (4WABS) Module, Brake Shift Interlock, Cluster and PCM Keep Alive Memory" Any idea where I should look from here?

 

IIRC the GEM stays energized for a period of time after truck shutdown. Wait 15 or 30 mins and check circuit again. It may not be your problem.

Hopefully someone will chime in with more specific knowledge of time and reason why.

 

I've been testing on it for the last 5 hours now. I've seen a lot of posts about draw on this fuse but nobody seems to post the solution. So far I've checked the glove box light, trailer connector, & alternator (all issue spots that I've read about) & yes I am leaving the truck sit to make sure the modules go to sleep. Does anybody have any info on having this same issue & what the fix was? I currently have 1.6ma of draw with the truck just sitting. Curious about the GEM but usually a bad GEM comes with other issues like locks or windows or power seat issues & I have none of that. Everything works fine in the truck & no weird sounds coming from behing the fuse box either

 

Check your tag light plug. just found a short in mine about a month ago. It's a Thunder Dome plug, Two wires go in, One wire come out. I just cut it out ran a hot and ground.

 

60mA is still pretty high.
How long did you let it sit to go to sleep? I'd let it go at least 60 minutes at least once just to get a base reference for what remains after everything goes to sleep.
When you are measuring this, is the door latch in the closed position? You can close it with the door open, just make sure to open it again before closing the door.
Door ajar light on dash?

 

Haha! Love that movie!

Break a deal, face the wheel!

Who runs Barter Town? Master Blaster Runs Barter Town!!!

 

Oh yeah, how about the hood light? I've forgot that guy once or twice.

 

Does you alternator feel warm even after the truck has been sitting overnight?

 

yes at one point I left the truck just sitting for over an hour with the meter hooked up to it & the lowest reading I got was 160ma. I had the doors open but the door latches flipped. No dome lights or dash lights were on, unhooked the hood light. I read about the alternator thing & to be honest I did think that it might of felt just a little bit warm but I unplugged it & still had the same draw, plus it is brand new, only a couple months old.

 

I ran some parasitic draw tests on mine today and found a good 95-100 mA going through the meter. That's high as I understand it, and what tipped me off was how closely I've been paying attention to the resting voltage on those new Walmarts I put in last week...just out of paranoia from recently having a dead pair of batteries and a no-start. Truck has been doing a lot more sitting that running lately, and after 4-5 days of that at a time, I come out to a resting voltage of only 12.4 or 12.3. A little concerning. It started fine...voltage came down to around 11 with the glow plugs and rose to around 11.6 before cutting off and jumping up to 14.4 when they shut off, so alternator is working fine and I verified with the meter both batteries were getting alternator voltage with the motor running. After a nice longer drive and motor off they show 12.65 or so again. (I loaded tested them and checked the voltage before I installed them last week to make sure everything looked right...it did.)

Clues: the alternator got some new bearings and a new voltage regulator at the rebuild shop about two months ago. And about a month ago I swapped the original PCM out with the hot tune on it for my stock-tuning backup unit. Possible trouble I caused myself here? Can I simply disconnect the alternator B+ wire and run the parasitic draw test again to rule out a wonky voltage regulator? I already disconnected the CTS2, Tekonsha P3 and even took the USB adapter out of the power port and now I will just leave the negatives off the batteries if the truck sits for a couple weeks after a drive. Not a big deal I'd likely even have noticed if the truck was started every day, but now I guess it's a mystery that needs solved.

 

https://www.autozone.com/ignition/ki...E&gclsrc=aw.ds

Get a pair of these things. They have been a game changer for me as my rig could sit at the airport for 3 or 4 weeks at -30F nights. Last thing I need are batts that have been feeding some mysterious current draw. Makes isolating/reconnecting the batteries a 10 second deal.

My old e99 had the random horn/interior lights thing going on, with the attendant current draw. The root issue was a corroded fuse box. Before I got dialed in to that fiasco, I had a mystery draw that turned out to be the heater fan. If the selector switch wasn't in the OFF position, the fan could come on, even if the fan switch is in the off/low position. I was tipped off on that one on a very cold, quiet, still night. It certainly explained why my batts kept running down.

Going back to the corroded fuse box, it is possible that there is a bypass to ground.

 

Those are an interesting idea. I wonder if Blue Sea or any other electronic gizmo companies make them. Bigger trucks and equipment that can sit unused for longer spells will often have a main battery disconnect. Car batteries will still self-discharge a little but 2-4 weeks at a time no big deal. (2-4 months a concern maybe.)

Today out of curiosity I disconnected the alternator and saw no change on parasitic draw...still around 95-96 mA. Have I successfully ruled that out? (hopefully).

I could of course swap the other PCM back in and see if that changes anything. I don't remember this being a problem till just recently, and those are the only two changes that have also been made recently that could be culprits (PCM and alternator)