Just thinking out loud here, in post 36 above, the connections to the black box you posted photos of, looks like it could be the heater/ac blower motor connections, so with the connector disconnected, you could see if that kills the blower motor & maybe answer that question.

I agree that it seems you have more than one problem & that its confusing your trouble shoot, so concentrate first on the item that's causing the most current drop, then look for the item giving next highest current drop as you remove fuses.

On the power mirrors remaining on, make sure the L/R switch is in its center position, so it kills power to the mirror motors, in case the switch has a welded contact.

On the fuel pump circuit, just because we can't hear it run doesn't mean we're in the clear yet. If the computer timing circuit doesn't fully turn/bias off & its timing circuit solid state switch is electrically leaky, it could still be trying to drive/run the fuel pump, but not put out enough voltage, or be able to take the current load to run the pump enough to hear, but cause a low amp drain, even with the fuel pump fuse pulled, because its electrical connection is After the fuel pump power fuse & power relay.
Think about it like an alternator rectifier diode junction that is electrically leaky, not fully shorted, nor high resistance/open circuit, but has enough contact from use, or damage, to draw a little current & drain the battery over time. This kind of scenario happens often with solid state things.
Murphy's Law says to suspect Everything, take nothing for granted, as when something goes wrong, it'll happen when it causes the most consternation & aggravation!!!! Boy how many times has that happened to me over the years!!!!
Not saying the fuel pump circuit is the problem, just that it, or problems like it belong on your suspect list until proven innocent.

I found a 94 electrical circuit that had some info about what's on fuse #17 besides the under hood trouble light, which you said earlier that the lamp had been removed. Looking at that info I also noticed that the 94 had its DRL = Daylight Running Lights fused through #17 too, so if you have DRL, put its module High up on your suspect list, as they're known to act out & under hood fuses #2, #3, #4 which you said caused the current to go back up when plugged in, were for the lights, so that DRL circuit or module would belong high up on your parasitic drain suspect list if your ride has it.

So, when you get back at it, first concentrate on the fused circuit that gives the largest current drop & try to fully investigate it before moving on.

More thoughts for pondering, let us know how the trouble shoot goes.

 

Many thanks again PawPaw. Now all I need is a day that temps are above the freezing mark. I'll redo some of what I've done then follow the your suggestions from there. Stay tuned for results.

 

Do you have DRL on this vehicle???? If so, put the DRL module at the Top of your suspect list, as it correlates well with the parasitic drain going up when you install fuses 2-3-4-17!!!! If no joy with the DRL idea, since all of these fuses are for the lighting circuit, look to an acting out turn signal blinker, stuck rear brake light switch, or if you have cruise control, a faulty brake master cylinder cruise control de-activation switch. On later models this switch which has B+ to it at all times & which had a rust red color center insulator, would leak fluid into the switch contact area, short out internally, get hot, boil the fluid & catch fire.
SO, after the battery has been connected for a while, feel that switch to see if its warm, even if it doesn't have the rust red insulator, (the ok ones had a black color center insulator). Disconnect its electrical connector to see if parasitic drain drops, replace it, no matter the insulator color, if you come to suspect it.
I had my 99 Rangers rust red switch replaced at my cost, even though it had no external signs of leaking/weeping brake fluid & the recall fuse harness installed by the Dealer/Ford under recall.
If you've installed any other lighting system mods, like an auto headlight dimmer, ect, on circuits 2-3-4-17, put them on your suspect list too.

 

No DRL on it and I have already disconnected both switches on the master cylinder with no change in draw. As a precaution I'll feel for the heating of the CC switch you mentioned. All lighting seems to be working properly as are PW and PLs and CC. Will check the power mirror switch next session once the temps get back above the current levels. This would be so much easier if we weren't in the dead of winter here.

 

OK, good feedback. Dang, no DRL, had convinced myself that would be it, as it fit so well with it being connected on the #17 fuse & all the other fuses being for lights. SO, stay focused on the lighting circuits, as that's the one common thread so far.
Lets see, thinking along that line, do you have a trailer wiring harness or electric trailer brake gizmo plugged in, if so, unplug those puppies & see what happens.

 

Did have a trailer harness but took it off a year or so ago. It was one of those that plug into the existing connectors type. When the opportunity presents itself I will concentrate on the lighting circuits by tracing each one if that what it takes. Between the dead ends and the cold weather its trying my patience but it takes more than dead ends to overcome hardheadedness.

 

Not really dead ends, they tell us something, we just have to be able to properly fit that piece of the puzzle in place, then step back & see if it gives us the clue we need to better zero in on the culprit.
All those fuses being for the lighting circuit is a good clue & it might be time to consider removing a fuse & using the battery charger to individually power each lighting circuit, to see which one has the drain.
Then begin a careful look at whats on it & the wiring condition.
Once you find a suspect circuit with current draw, you could go to each lamp & pull them one at a time to see which part of the circuit has the problem & that way narrow things down & eliminate a lot of wiring runs to inspect.
More thoughts for pondering, hang in there, the end is neigh

 

A little off topic. But I had this exact problem on a Jeep GC. I was a combination of 2 fuses used by the alarm / security system even though it had been disconnected. I think you mentioned something about a security system. If so check that it really close.

 

Thanks wtroger but unfortunately I don't have a security system. My hunch is Paw Paw has me on the right track based on the fuses that appear to control the draw. Interestingly, yesterday I had occasion to follow the truck while the wife was driving and noticed the upper brake lights were not working. I had checked the others but hadn't noticed the high ones. That will be priority #1 once the weather gives me a break.

 

Had the opportunity to get on it yesterday with the following findings. I don't believe my charger to be the correct variety to use to trace individual circuits but I did notice some interesting results by pulling fuses and relays. First off, when I pull every relay and fuse in the PDB the draw drops to 1.76 amps. I can then replace all three relays, fuses #1, 6, 15, and the diode with no change in that 1.76 draw. However, if I plug back in any one of the following fuses: #3, 4, 2, 17, or 16 the draw returns to 3.56 level. #3 is labeled "fuse panel", # 4 is EEC power, #2 fuse panel, #17 is the under hood light and #16 is alternator.

 

What happens to the remaining 1.76 amp draw if you disconnect the EEC???

 

I didn't check that the last time but I did several attempts earlier with the 3.56 draw indicating on the ammeter, it didn't make any difference when I unplugged the EEC then. Would... or rather could there be a difference with all the fuses and relays pulled?

 

Well maybe, as we don't know where the draw is coming from & thinking maybe you may have more than one parasitic draw problem.
As removing the lighting fuses only takes away about half of the draw, something else is awake too & the computer is a good suspect & its quick & easy to trouble shoot, by disconnecting its firewall electrical connector to see how much if any, the remaining 1.76 amp current draw drops.
After everything goes to sleep, we should have something like 50ma or so draw, from things like the clock, radio memory, ect, so it never all goes away.

 

Got that, tomorrow there is a break in the low temps so I'll redo the test with the meter in the circuit... then disconnect the EEC and see what happens. Stay tuned for update. Thanks again.

 

I got the chance to recheck the EEC yesterday but results were the same. All fuses and relays out of the PDB, disconnected both leads to the EEC but draw was not affected. Interestingly though was the fact that the draw with all fuses and relays removed was higher than it had been previously. The truck had not been started since the day before. The previous testing indicated a draw at about 1.76 amps., yesterday, at warmer temps, the draw was 2.25 amps. Could that difference point to anything in particular?