Drop the tank. Remove the fuel pump/sending unit/hanger assembly. Reconnect the wire harness to the hanger assy.
Turn on the ignition. Move the float up and down, watch the gauge. When the float is up, the gauge should be "Full". When the float is down, the gauge should be "Empty".
If it doesn't, either the sending unit is bad, or the wire harness is faulty. THAT gets diagnosed separately.
Turn on the ignition. Move the float up and down, watch the gauge. When the float is up, the gauge should be "Full". When the float is down, the gauge should be "Empty".
If it doesn't, either the sending unit is bad, or the wire harness is faulty. THAT gets diagnosed separately.