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Technology Electronic device Auto part Automotive lighting Electronic component
Electronics Electrical wiring Technology Electronic component Electronic engineering
Checking your fuses with a test light is really quick and easy.
Simply ground the test light lead, and touch each side of the fuse with the probe end. If it lights on one side, It MUST light on the other side, or it is bad.

If it doesn't light on either side, try turning the ignition key to ON/RUN. Now at least one side should light up. If not, it might be a spare, (unused) fuse.

You can find your fuse panel descriptions under the "roadside emergencies" section of your owner's manual. If you don't have a manual you may download a 1996 and newer one for free from here

If you don't have a test light, you may pick one up at a $ Dollar store for a Dollar.

You may also use a volt meter. Just ground the neg pole, and test each side of the fuse as noted above. You should have battery voltage on both sides of the fuse.

Please note: Often one fuse in the battery distribution box (under the hood) may supply many fuses in the Central distribution box (inside the cab fuse box). Therefore if many fuses inside the cab do not have power, it may be because you didn't turn the key to ON, OR there may be a blown fuse in the under the hood battery distribution box.

Please see the photos below for additional info.
 
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This doesn’t make sense. Do you mean that after pulling the fuse, both sides of the now open fuse location on the fuse panel should light up with the test light?
 

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Joseph51

The above post explains how to check a fuse with OUT removing from the fuse box!

If you remove the fuse there should be power to one side of the fuse holder. (With the circuit turned on, may require the key to be in the on position)

However with the fuse pulled one can NOT tell if the fuse is good using the method above. With the fuse removed, using a visual method or using a ohm meter will tell if the fuse is good.

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Is there any reason not to use an Ohm meter to check fuses without removing them? An Ohm meter shows continuity or lack thereof. If voltage is present, can the Ohm meter be damaged?
 

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yep. don't use the ohmeater on powered circuits. the meter may show continuity, but that can be a microscopic connection. when power is applied no current flows. best to check with current flowing with voltmeter or test light. comparing volts in to volts out can show you a voltage drop that will cause heat
 

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Never use an ohm meter on a live circuit, Yes it will damage the meter very fast.

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