Fuel Gauge

Remove the instrument cluster.
Check the fuel gauge by changing the resistance between the terminal.
Apply battery voltage to the terminal 2l, ground the terminal 2h, and connect the resistance to the terminal 3k and then check that the pointer is moved as shown in below table.

Fig 1: Testing Fuel Gauge
Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: Fuel Gauge Resistance Chart
Courtesy of KIA MOTORS AMERICA, INC.