Ok. I'm back with another question for you gurus.
I used a 6 way fuse block with LED indicator that turns on via a switch to the stinger. So I got a little OCD and was using the fancy little stickers to label the fuse block circuits. (winch, radio, turn signal kit, etc). I was doing this by a process of elimination, meaning all the wires were zip tied and loomed up and a little hard to trace. So I pulled fuse, and see what didn't work. This worked until I got to the radio. Typical radio, 1 yellow wired to battery for clock memory, red to switched power when you want it to come on. So with the fuse pulled, radio still was on? WTH?
So I tested fuse block with circuit tester. 12.8 volts with power on and fuse in, 9.8 with fuse removed.
After a simple Google search, I found that this is normal, but doesn't let much amperage through. However, it is enough amperage to still turn on the radio (I guess because it pulls main power from yellow wire). But not blinkers, winch, or anything else so far. If I remove fuse for those items, which have a bigger amperage draw, they do not work. (as expected)
Anybody else have this happen? Any idea on how to fully "break" circuit as if the use was blown? Concerns me that if the fuse ever did actually blow! Then perhaps my radio might have permanent damage issues if ran for a period of time on less voltage.
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That "leakage" voltage and current is going through the diode and it's current limiting resistor, which is in parallel with the fuse. When the fuse is not blown, it shorts across the led/resistor, so it doesn't light. When the fuse is blown, the LED conducts through the current limiting resistor then through the load (radio in this case). Not sure of the size resistor, but say is 1K Ohm. That would result is about 12 mills (milliamps) of current through the load, if the load was a dead short, which it isn't. That may be enough to light an LCD display on the radio, but the radio can't operate with on such a small current limited voltage, nor would it be likely to damage anything.
I didn't like that aspect of the "warning light" fuse panel, so removed that circuitry. I'm old school and can figure out which fuse is blown without the idiot light.