Display Problems
There are several main conditions or sources of possible interference that may cause problems with the quality of the information displayed on the control head. Look in the following table for some symptoms of display problems and possible solutions:
Problem | Possible Cause |
The control head loses If the power output of your boat’s engine is
power at high speeds. unregulated, the control head may be protecting itself using its
Finding the Cause of Noise
Electrical noise usually affects the display with many black dots at high speeds, and high sensitivity readings. One or more of the following sources can cause noise or interference:
Possible Source of Noise | Isolation |
Other electronic devices | Turn off any nearby electronic devices to see if |
| the problem goes away, then turn them on one |
| at a time to see if the noise |
The boat’s engine | To determine whether the boat’s engine is the |
| source of the noise, increase the RPMs while |
| the boat is in neutral and stationary to see if the |
| noise increases proportionately; if noise appears |
| when you rev the engine, the problem could be |
| the spark plugs, alternator, or tachometer |
| wiring. Replace the spark plugs with resistor |
| plugs, install an alternator filter, or route the |
| control head power and transducer cables away |
| from the engine wiring. |
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