Help finding a short, Who's good at ELECTRICAL???

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fast 99

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Some items in vehicles don't have a draw until after they have been powered up. So you have to unhook battery, hook up meter,amps, turn on key, turn off. If your meter only does 10A, make sure you don't have a bunch of crap turned on when doing this, -heater, wipers, etc, bot DO turn on radio, especially if aftermarket. This is why mechanics use a battery switch, install it, run vehicle, turn everything on, turn truck off, hook up meter across disconnect switch, open switch. This way everything gets activated.
You just made confirmed my case for using a shunt. Very easy to exceed 10 amps.

Will add a majority of draws I have seen were caused by aftermarket items, such as alarms, remote start, radios, amps, ect.
 

Ricko1966

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I will once again state it is nice to make a lead for your meter with an inline fuse lower than the meter fuse,cheap,easy to check,easy to change.
 

Nasty-LSX

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Last thing I can think is did you blow either of the fuses and is that making the meter not read?
Good luck!
Im willing to bet your right. When I first started even before I made a post. I had the MM set up just like in the
video on 10A and leads were located all correct. When I placed one lead on the negative battery cable and the other lead on the battery post, it sparked pretty good. (lead tips) both. How do I find out what fuse to change out?
the 10A does not look blown. is it supposed to change colors or something. I also took the plug out the alt and will see tomorrow if batt is drained.

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Nasty-LSX

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I will once again state it is nice to make a lead for your meter with an inline fuse lower than the meter fuse,cheap,easy to check,easy to change.
Im going to do that! :happy160:
 

Ricko1966

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Im willing to be your right. When I first started even before I made a post. I had the MM set up just like in the
video on 10A and leads were located all correct. When I placed one lead on the negative battery cable and the other lead on the battery post, it sparked pretty good. (lead tips) both. How do I find out what fuse to change out?
I also took the plug out the alt and will see tomorrow if batt is drained.

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If you had a meter you could check resistance of the fuses. 0 is good OL is bad. If you do not have another meter,a piece of wire a dome light bulb and three hands.With the 10 amp fuse one end set on negative battery cable hold the wire pinched to the other end of the fuse. Hold the wire to one end of the dome light bulb touch the other end to the positive battery post. If the light lights the fuse is good,if not check to make sure you are making contact everywhere if still no light, fuse is bad. If the fuse is good measure resistance of the other fuse if it reads open put your 10a fuse where the other fuse was,read the fuse again. Still open that fuse is bad.
 
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Robert Bare

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The big fuse on the right is the amp, and is sealed, have to check with a meter or such. Your meter will still work on volts and ohms, use it to test the 10a one after you take it out.
PS, when an alt. goes bad, as far as causing a draw, is usually a diode, and unplugging the little wires will tell you nothing, you have to remove the big cable from the back.
 

Broken85

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I know you said this truck is stock and unhacked, but what’s the story of this box?? Is that a snow plow relay or something? Looks like maybe something after market. Also, I assume this is a single battery set up, but if it’s not, are both batteries good?? One bad battery will ruin both of them. With that kind of draw, a test light should shine like the sun between the battery and the terminal. If it’s bright, it ain’t right. If you have an IR camera you can also check for heat under the hood on a cold morning to see what is on and drawing current
 

Nasty-LSX

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I know you said this truck is stock and unhacked, but what’s the story of this box?? Is that a snow plow relay or something? Looks like maybe something after market. Also, I assume this is a single battery set up, but if it’s not, are both batteries good?? One bad battery will ruin both of them. With that kind of draw, a test light should shine like the sun between the battery and the terminal. If it’s bright, it ain’t right. If you have an IR camera you can also check for heat under the hood on a cold morning to see what is on and drawing current
Single battery. That box is a Blue Sea fuse box as a stand alone for my 2 front fans with relays. power comes from the side terminals on the battery and 2 toggle switches on the dash for control. :happy160:

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Grit dog

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I think the little fuse is like 1/2amp for the lower settings.
And it should work on ohms you can test the fuse.
Or pop another fuse in it if you have any old glass fuses. Preferably 10A or less for obvious reasons.
 

Grit dog

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Single battery. That box is a Blue Sea fuse box as a stand alone for my 2 front fans with relays. power comes from the side terminals on the battery and 2 toggle switches on the dash for control. :happy160:

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I like those little Blue Sea fuse boxes. I put the same on the K20 for accessory loads.
 

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