Floscan gauge odd behavior

[robinsbd]

When I turn the ignition key to the ON position with engine not running, the Floscan gauge needle goes crazy and flutters between zero and pegging. The needle really pegs hard too and you can hear it when it hits the stop at maximum.

Any ideas on how to troubleshoot this?

The actual fuel flow sensor is inline of the fuel line between the water sep filter and the mechanical fuel pump on my engine.

 

[TunaFish389]

Unhook from sensor and see if issue continues. If issue stays with gauge then gauge going bad. If issue stops the sensors going bad.

Or maybe wiring has a short which you can ohm.