Red light on fuse hoder

[Karnic]

Hi All. Appreciate your kind help. I was washing boat and was trying on the electronics. As soon as I switched on the bilge switch the red led on fuse holder ( see photo) lit and made a hiss sound. Tried to switch it on by lifting the bilge lever to no avail. Didnt work. However after a couple of minutes i tried again and bilge worked normally via switch and even manually. Could it be fuse was blown? If so will changing fuse ONLY solve issue? As said now bilge is working but not sure if fuse is still ok. What should i check?

 

[EugeneR]

Yes, change the fuse, maybe pump as well.

The LED goes on when there is a voltage drop over the fuse. The pump might work weakly because, for the LED to work, it must allow a small current to pass. I'd have expected that current to be too small, though. There should be a resistor to limit LED current which will cause a voltage drop, which will prevent significant power being pulled.

The question though, what caused the fuse to go? Did it work as expected i.e. due to short within pump or wiring, or is the fuse bad?

Having been on offshore in a boat filling with water and seeing the bilge pump burn out while in use - I'd replace both.

 

[Karnic]

Thanks for your input and help. Yes that's my concern. Honestly the thing that is baffling me is that Bilge is working normally ,when via switch i.e. when batteries are on, and manually i.e. batteries are off but as obviously bilge is wired directly with the batteries even when off , it is working. Took the fuse to an electrical shop and was told fuse is still good and bought another one just in case. Could it be just a bit of a slat build up near the intakes that cause the issue. As said when switching bilge on red LED on fuse holder LIT and a strange HISS sound was heard. After a couple of minutes tried switching both ways( via switch and Manual ie lifting bilge lever) and worked fine

 

[emmalina]

Probably muck in the impeller.

 

[EugeneR]

I expect the pump to have 3 wires going to it:

1. Ground
2. Red supply via fuse and then via float switch. This automatically takes care of water in bilge.
3. Another supply, possibly orange, via a fuse and manual switch located in a remote location.

Supply via 2 and 3 are independent ways of making the pump work.

So, if it works by pressing the remote bilge button, your testing possibly excludes the fuse shown, and the float switch.

Hissing in the water / pump suggests water between exposed wires in the pump, as part of route 2 above.

The new fuse should clear the LED. Does it?

(Interesting on mine, and just this contributes here, there was a dashboard warning LED beyond the remote switch in path 3, that would go on when path 2 was activated i.e. via float switch. Of course, when float switch is activated, the current goes "the other way" via route 3 to the output side of the remote switch, where the warning lLED would then go on when either switched on the panel or by water in the bilge.)

 

[billskip]

I woud check the connections, in particular the -ve return to the battery...

It should be battery +ve to fuse to auto float switch to pump...then pump -ve to battery.
The manual hand switch is an override switch that is in parallel with the float switch.
If the fuse had "gone" it should not be able to work

 

[Alex_Blackwood]

I woud check the connections, in particular the -ve return to the battery...

It should be battery +ve to fuse to auto float switch to pump...then pump -ve to battery.
The manual hand switch is an override switch that is in parallel with the float switch.
If the fuse had "gone" it should not be able to work

+1 for that. More likely you have dodgy connection(s) in the circuit. Would put bets on the fuse holder. The pump will not work if the fuse is blown.