Working with a Regina fuel sender NON READING gauge problem.
Sender unit is out of the car, and I have had it apart and examined. The float contact points between the rods are OK, the pads are intact and the float moves up and down the rods as the unit is turned up and down. Measuring the resistance, however, there is no change with the float up or down (Full/Empty), the reading being around 180. The readings also jump around a lot, difficult to get a nice steady number on the display of the multimeter. All else seems fine, the wiring, etc. The rods' windings obviously have connectivity and are not broken. Why then does the measured resistance not change with the movement of the float?

The gauge tested OK using the 68 ohm resistor.