Partially malfunctioning fuel gauge panel | help!

[jdd01257]

Hi! And Merry Christmas!!

2015 31’ marlow Hunter with Yanmar engine here in So Cal. Out of the blue, the fuel gauge stopped functioning along with the sensor for the engine compartment fire extinguisher (the left side of the panel). The right side is a high water bilge alarm which still works.

I suspect, due to Marlows poor placement of this right beneath the cabin top water runoff groove, that there could be water ingress resulting in corrosion, and so I took out the panel but the connections look good.

I’m no electrician but am willing to learn to diagnose myself with a multimeter (just not confident I’d know how to read it correctly resulting in a false negative of some sort).

and yes, there’s fuel

pics attached if anyone has any suggestions!

 

[jssailem]

The system is simple. There is a sensor on the tank. You need a connection “ground” and a positive line. Check that they are clean and properly connected to the tank sending unit.

This is often weakness.

 

[jdd01257]

Thanks for the reply. Haven’t checked tank connections yet - just the ones here on the panel and they seem fine.

but it’s weird that the fire extinguisher sensor ismy working either - while the bilge pump one is...

 

[jssailem]

Yes. This is what leads me to question the ground connections.
How previous workers or owners make ground connections sometimes causes disassociated systems to fail when the ground becomes intermittent or stops working.
As they say look to the simple things, the usual suspects. Ground connections fall into that category.
Looking at your image of the engine panel. Nothing appeared to be out of place or obvious issue.

Good luck

 

[twalker H260]

Have you checked that the fire suppression system itself has sufficient pressure? On many hunters If the system has low pressure it will disable power to the cockpit engine controls.

 

[MikeHoncho]

When multiple things stop working at once I first check the common ground.