Furuno CH-270 Installation Manual page 26

Assembling of Hull Unit CH-181-270 (350 mm stroke)
BEFORE beginning the installation turn off the breaker inside the hull unit as shown below.
Turn it on after completing the installation section.
1. Unfasten six screws to remove the cover from the hull unit.
2. Turn off the breaker switch. Close the cover.
Breaker
Switch
14
Unfasten six screws:
two on top and two
on each side.