I have a 2003 Ranger which I drive only occasionally. As a consequence, I routinely have dead batteries. The passive drain is 44 milliamps. Is there a fuse I could remove rather than disconnecting the battery while the truck is parked?

 

You'll need to get an ammeter out and test each fuse to see where the drain is. Once you identify that (those) fuse(s), that is (those are) the one you'll need to remove.

Keep in mind if it has anything to do with the computer, you may have to drive the truck several times while it relearns some things.

Personally, I'd just hook up a trickle charger when it's going to set for a while.

 

Battery should last 10 months or more with only 0.044amp draw, 44mA

The 3 key OFF draws on a 2003 Ranger are
The radio, that holds clock time and presets
The computer, that holds "learned" data, i.e. idle levels, past EGR and EVAP levels, and fuel trim data
And Keyless entry(Fobs) it has to stay on "listening" for a command from a fob to unlock or lock doors

So there would be more than one fuse to pull, in engine bay and cab fuse boxes

Better option would be to install a Battery Cutoff switch on either battery terminal, usually just a **** you rotate by hand that disconnects that battery terminal from the battery cable, easy to install and use


If battery goes dead after only a few weeks to a few months then most likely the battery itself is the issue
Disconnect battery from vehicle
Test its voltage and WRITE IT DOWN, leave it for a week or two then retest, should be EXACTLY the same voltage, any less means battery is self draining

 

A Battery Cutoff switch!! Didn't know there was such a thing. It should do the trick.

 

Just remember your computer will have to relearn a lot of settings.

 

But if battery power is disconnected then your vehicle computer can survive a Nuclear strike EMP, so there is that going for you, the only running fuel injected car in your area, lol


The relearning is not that big of a deal, wandering idle is about all you would notice, and of course the clock flashing 12:00, lol

 

Have a 3Wire120vLanyardCord anchored to the GarageWorkBench in front of my 2001, MaleEnd plugged into a 120vPowerOutlet,
the other FemaleEnd plugs into a 3pinMaleChassiSocket with SprungClosedProtectiveCover mounted in the Grille,
that in turn is wired to a 120vacTo12vdcMiniTrickleCharger mounted under the Hood next to the Battery.
During colder winter months, both Wife & I don't drive icy\snowy roads unless we absolutely need to,
so the vehicle may sit for several days, but this arrangement keeps Battery ready to go;
as I back out of the Garage the Lanyard "automaticly unplugs" from the Grille mounted ChassiSocket.
The ChassiSocket & Charger are small enough to not be noticed or interfer with other items.
Use this truck to plow a long driveway & part of the county road, using a drag plow;
a fully charged battery during a blowing snow storm is always a good thing.

 

100% incorrect. Whether the battery is connected or not, the computer is still 100% subject to the dangers of an EMP. The only thing disconnecting the battery will do is reduce the amount of wiring (the internals of the battery) that will act as an antenna. Doing so may increase the odds of the computer not getting fried by a factor of 1 or 2 percent.

Fact is, computers sitting on a shelf at the auto store are just as susceptible to an EMP.

 

Unless your vehicle was right next to the Nuclear blast(in which case EMP would be a moot point, lol), then your vehicle electronics have a much better chance of surviving an EMP if unplugged from the battery
Metal vehicles(like metal aircraft) are similar to a Faraday cage so offer some protection against EMPs(and lightening) just because of that, no Grounding needed(i.e. rubber tires)
While any wiring can get inductive current from an EMP, the unpowered, terminated and short wiring in a vehicle wouldn't be "good" antennas
The longer wires in a vehicle are hooked to the lights, not the electronics

While my original comment was made in jest, it for sure wasn't 100% incorrect, lol

 

Unfortunately, there is no one single 'type' of EMP. Nor is there any one frequency or narrow band of frequencies for an EMP to propagate on. As such, there's no way to predict what 'an EMP' will do to any consumer electronics given there's zero research on the matter. As such, there are no hard-and-fast rules as to what will and will not be effected.

The innernets is full of 'proofs'. Lots of people put an AM radio in a microwave and since they can't hear the local radio station when they close the door, they claim a microwave is a perfectly good Faraday cage. But a simple household microwave totally disproves their experiment. Ever look through the door of your microwave to see if you pizza cheese is bubbling? Hmmm.... microwaves are part of the electromagnetic spectrum, as are the light waves produced by the light bulb inside your microwave. So if a microwave is a good Faraday cage, how can you see the light coming out of it?

The holes in the door of the microwave aren't just randomly created. They're a specific size, small enough to block the longer microwave frequencies but allow the shorter wavelengths we call 'light' to pass through. Simply physics.... the shorter the wavelength, the smaller the hole it takes to block it. Get to a certain point, and a tiny little pinprick in a Faraday cage can allow a high frequency to go through and, given sufficient strength, can damage any electronics inside.

Yes, a metal body provides some protection. But there's less and less metal in vehicles every day, being replaced with composites. But given that an EMP is composed of several bursts of different frequencies and various durations, I wouldn't count on disconnecting a battery in a vehicle alone to protect it.

As for the length of the wire (short wires to electronics, longer ones to lights), stop and think what controls the lights.

A good read on EMPs, as well as CMEs and GRBs, is EMP Attacks and Solar Storms by Arthur Bradley.

 

I think we have gone off topic, lol

 

If driving down the road & you see this thru your FrontWindShield or RearViewMirror,
quickly pull over & stop, pop the hood, & disconnect your battery;
wait roughly 10,000 years until radiation has dropped to a survivable level,
then re-connect the battery, re-start your engine & continue on down the road normally!