If your fish finder screen appears black, blank or another solid color when connected to a trolling motor with Built-In MEGA Down Imaging (MDI), check the fish finder software, Connected Transducer setting, cable connections and transducer position. A screen that appears blank while the trolling motor is stowed may simply indicate that the transducer is out of the water.
Jump To:
- Update the Fish Finder Software
- Check the Connected Transducer Setting
- Check Transducer Connections
- Check if the Transducer Is in the Water
- Turn Sonar Off When Stowed
- Resources
Update the Fish Finder Software
Make sure your fish finder has the appropriate software installed.
HELIX G2N models require a software update to function correctly with Built-In MEGA Down Imaging.
Check the Fish Finder Software Updates page for the update available for your model.
Check the Connected Transducer Setting
For HELIX fish finders:
- Open the Sonar menu.
- Find Connected Transducer.
- Confirm it is set to Built-In HW : MDI+.
Check Transducer Connections
Check the complete connection between the Built-In MEGA DI transducer and your fish finder:
- Inspect the transducer adapter cable connection.
- Make sure all connections are secure.
- Check the transducer connection inside the trolling motor control box.
A poor connection can cause a loss of sonar signal.
Check if the Transducer Is in the Water
If the Built-In MEGA DI transducer is not submerged, the sonar display may appear:
- Black
- White
- Green
- Red
- Blue
The color displayed depends on the selected sonar background color.
Turn Sonar Off When Stowed
It is recommended to turn sonar off when the trolling motor is stowed or the transducer is out of the water.
To turn sonar off:
- Briefly press the POWER key while the fish finder is operating.
- From the menu that appears, turn Sonar Off.
Turn sonar back on when the trolling motor is deployed and the transducer is submerged.
Turning sonar off while the transducer is out of the water also saves power, reduces operating hours on the control head and transducer and reduces the time required for the fish finder to reacquire the bottom after the transducer returns to the water.
