Water tank gauge on Beneteau 40 (2009)

[JohnB40]

The gauge is one that only shows on the panel as 1/4, 1/2, 3/4 or full. So I don't think it has a float type arm in the tank, but maybe some electrical contact at these specific levels. Problem now is when full, it only shows 3/4. So I've lost that last "connection". The display is one of those solid lines on white background.
Any idea what mechanism sends the signal to this gauge.
Thanks
JohnB40

 

[Davidasailor26]

You’re correct that the VDO panel uses contacts at different levels in the tank to sense the water level. The voltage on a wire in the back of the panel will vary depending on how many contacts are submerged. You should see the wires going to the sensors on the outside of the tank somewhere. Attached is the manual for the panel which might help with troubleshooting.

 

[RoyS]

Consider using a battery operated meter to track water consumption. Reset to 0 after filling tank. Less than $30 and simple installation last time I bought one. Install in 20 minutes. Very accurate.