Thank you so much for your involvement with the Owner's Club Forum! We hope you've gotten some great information and had the chance to interact with other owners on the current system.

How to troubleshoot a faulty fuel gauge part 1

topcat Member Posts: 13 ✭✭
An easy way to troubleshoot the fuel tank sender, fuel gauge, and wiring harness to determine if a component is faulty and needs to be replaced or another problem exists that renders the gauge inaccurate is as follows.

To properly diagnose the fuel measurement system the use of a DVM or analog Ohm meter is required, there available for a couple of dollars if you don’t have one. Turn off the power to the batteries and locate the deck plate access hole to the fuel tank sending unit which is located at the top of the fuel tank.  On my 2013 Sundeck 2200DC the deck plate access hole is to the left of the captain’s chair. Once you locate the fuel sender unplug the two wire mate and lock connector with the black and pink wires.  Using an Ohm meter measure the resistance of the fuel sender located in the tank by connecting the black meter lead to black and red meter lead to the pink wire on the short sender wire harness.  Record the value you obtain.

The sender unit inside the tank is a long rod with a float that looks like a donut that floats up and down on a 1” rod.  When the float is all the way to the top of the tank (tank is full) the sender must measure 33.5 ohms.   When the tank is empty the float is at the very bottom of the length of travel and the resistance reading will be 240 ohms. You will get resistance value readings in between 33.5 ohms and 240 ohms for other fuel tank levels.   Essentially the sender is a simple variable resistor called a “potentiometer” that is adjusted by a float.    Reconnect the harness to the sender. Next remove the instrument panel and unplug the connector wire from the fuel gauge and use your meter to measure the black and pink wire. On some huuricanes you can get behind the instrument panel from a storage locker and avoid remobing the dozen or so short screws securing the instrument panel to the console.