Aftermarket fusebox with LED light for blown fuse

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mshaw1980
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Aftermarket fusebox with LED light for blown fuse

Post by mshaw1980 »

Hello

Just need to check something with the above fusebox I have fitted to run the leisure battery circuit. To me it's odd but when the fuse blows the circuit still works albeit at a reduced voltage. For example, the led lights were on and I accidentally shorted the terminals on the switch which blew the fuse identified by the illuminated light on the fusebox however the lights still worked but noticeably dimmer. Is this normal with these fuseboxes or do I have an earth leak?
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

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Oldiebut goodie
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Re: Aftermarket fusebox with LED light for blown fuse

Post by Oldiebut goodie »

I will hazard a guess - you need an earth to get the fuse led to light which it gets from earthing via the rest of the circuit ( your led lights). Normally the led will not light as the voltage is the same either side of it.
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tonytech
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Re: Aftermarket fusebox with LED light for blown fuse

Post by tonytech »

I think the led on the fusebox is just wired accross the fuse with a suitable resistor in series.
Fuse OK ... current flows through the fuse to the circuit as normal.
Fuse blown .. current flows through the led and resistor to the circuit... The resistor limits the current to a few mA so no overheating or burning wires.
If, as in your case, the circuit only needs a few mA to power it the "blown fuse indicator" will pass enough current to light your lights.

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mshaw1980
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Re: Aftermarket fusebox with LED light for blown fuse

Post by mshaw1980 »

Thanks guys :ok
1987 VW T25: Subaru EJ20 using RJES parts (If it was meant to go fast it wouldn't be brick shaped!)

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