Something has been draining my batteries. I traced it to a wire that supplies power to the fuse block on the driver side fender well inside engine compartment. It pulls .5 amp and I can't find it.

Test were done with amp meter between neg post on one batt and neg bat cable. Other battery is completely disconnected.

I unhooked everything from battery and then hooked up wires at relay one at a time until i found one with a draw. Turned out to supply power to fuse box on other side of engine compartment.

Moved meter to other battery leaving only one wire hooked to relay and pulled all the fused and relays. NO change.

I turned key on and have no power anywhere in cab.

What will pull power but not go through a fuse???

Does it feed on to the inner fuse panel?

Any suggestions on where to look?

 

I found it. And I lost it Its fuse. It's Maxi fuse S which said see fuse 4, 8, and 16. Also see Circuit breaker 12.

Only problem is it's not drawing power now. I pulled it in an out several times and watched the meter go up and down. I went to move the meter around the other side of hood so I could see it from inside the truck. Pulled the cover off the inside panel. Got my paper to check and see which fuses to check and glanced at amp meter and realized it read zero.

No blown fuses. meter connections good. Wiggled wires. Door. Truck. Thought about my big hammer in tool box. I give up for today.

 

Maybe it was a little bit of corrosion or gunk on the fuse, or in the fuse block that was shorting across the fuse and causing the draw. Pulling it in and out a few times might have cleared that up.

 

Fuse S supplies power to:

fuse 16 -
cig ltr

CB 12 -
power door locks
power lumbar switch (if your seats have that)
Elec. shift control mod. (if your transfer case is elec.)

Fuse 8 -
Engine comp lt (was the hood light on?)
Pson inst clustr (that will draw less then a mA)
Radio (that can draw a bit when power is first applied, could be what you saw, will draw less then a mA when off)
Glove box
Door switches (was the interior light on?)
inside cargo light
Power mirror switch
Map/dome light
Courtesy light

Fuse 4 -
Running lights (that would be several amp draw.

If you have an after market stereo in there, they will always cycle the cd mech when power is first applied which could be what you were seeing on the meter.

Also does the truck have a remote start or alarm in it? they can go bad and kill batteries.

 

Not likely, that fuse would be getting rid of 6Watts of power, it would get pretty warm and look all melted or discolored.

 

Went looking for it again today. Couldn't find it at first and was giving up and putting wires back on solenoid when one sparked a little bit.


It was drawing from the 2 red wires that become one and go to the glow plug relay this time. It was 2 white wires yesterday. I'm thinking it might be in the switch or relay that is just not turning the power off. Its pretty strange that its a different wire.

I looked up ignition switch on auto zone site and it showed me a large square box that looks like a giant relay. Where does that go. I was expecting something you would shove a lock and key in.

Considering just running everything through a 100amp relay and put a toggle switch in dash. Key would just be to start it then.

relays continuous duty 12 volt & 24 volt DC power relays,starter relays