Fuel Guage

[SportsterDoc]

Generally, yes,... it also might be mechanically stuck (interference) from 1/2 to full tank, while working OK from 1/2 to empty.
If I remember correctly, fuel pump ass-y unit has a 4 pin square black connector.
How about 1/2 - 3/4 fill and shaking CB sideways , and then top it up, as a very simple test, without electrical knowledge. I do not think meter will show changes while shaking.
So try it if you want, does not cost anything.

I think the signal is buffered and needs time to change.

My 2014 standard is very consistent:
Each segment is about 0.6 gallon, until the last segment.

I did not follow Johnny's "issue". Did it still read "1/2" (3 segments) after completely full?
If so, float rod is likely obstructed or damaged, especially if something thrust into its path.

The dealer can probe the voltage output.

I think the signal is buffered and needs time to change.

My 2014 standard is very consistent:
Each segment is about 0.6 gallon, until the last segment.

I did not follow Johnny's "issue". Did it still read "1/2" (3 segments) after completely full?
If so, float rod is likely obstructed or damaged, especially if something thrust into its path.

The dealer can probe the voltage output.
My standard 2014 is very consistent as well. I always assumed each bar is a half gallon making up the first 3 gallons and then when the final bar switches to blinking that is the remaining .8 gal of "reserve".

I use trip 1 for refueling and trip 2 for day's outing.
Miles traveled will vary, average MPG will vary, but if I filled to bottom of filler neck ring, when first segment disappears, gallons consumed will be 0.6.

Second segment disappears, gallons consumed will be 1.2

Third segment disappears, gallons consumed will be 1.8