Self Test; Accessory Test - Humminbird 561 Operation Manual

Self Test displays results from the internal diagnostic self test, including unit
serial number, Printed Circuit Board (PCB) serial number, software revision,
total hours of operation, and the input voltage.
Accessory Test lists the accessories connected to the system.
NOTE: The speed accessory will be detected only if the paddlewheel has moved since your
Fishfinder was powered up.
Self Test Screen
System Status Accessory Test Screen
32 Start-Up Options Menu