Humminbird ONIX Operating Manual page 212

settings
Open the Fuel Tool
1. Press the HOME key.
2. Select the Fuel tool.
Refill the Tank(s)
1. Open the Fuel tool, and select Refuel.
2. To fill the tank to the top, select Fill Up.
To add an amount to the tank, select Add Fuel. Use the on-screen keyboard to enter the amount and save it.
NMEA 2000 Setup
Setting up Fuel Tanks Manually
Displaying the Fuel Tool
212
select Manual
select Fuel Capacity
to enter data
manually