How to Troubleshoot a Humminbird 100 Depth Finder

How to Troubleshoot a Humminbird 100 Depth Finder
You can save time by troubleshooting your Humminbird 100 Series Depth Finder yourself. Designed for anglers who require an affordable price tag and compact design while sacrificing few of the features of more expensive models, the 100 series offers an easy-to-use interface in two models. Whether your preference is for the single-beam sonar of the 141c or the GPS-plotting features of the 161 Combo, these devices can provide you with an advantage when seeking fish. As with any electronic device, performance problems occasionally arise. Knowing how to respond will mean a quicker return to casting.

Instructions

Difficulty: Moderately Easy

No Power

Step 1
Check the power cable to see if it is properly connected to the control head. Make sure the red line is attached to the battery terminal's positive end and the black line to the negative end.
Step 2
Verify that the power connector has battery voltage of at least 10 volts.
Step 3
Inspect the fuse to make sure it is functioning properly.
Step 4
Clear corrosion from the battery or terminals as needed and replace the battery, if necessary.

Defaults to Simulator at Power-Up

Step 1
Inspect the transducer cable to determine if it is securely fastened to the fish finder. Disconnect and then reconnect the cable before pressing the power key.
Step 2
Check the transducer cable for signs of wear, such as corrosion or other damage.
Step 3
Insert a working transducer to determine if the problem is in the transducer or the cable.

Noise Interference

Step 1
Identify possible sources of noise that may be disrupting the fish finder during high speed or sensitivity.
Step 2
Inspect the positioning of the transducer, as propeller turbulence due to improper positioning can create interference. Readjust the positioning of the transducer if it is closer than 15 inches to the propeller. Adjust the transducer so water flows smoothly past it at all speeds.
Step 3
Switch off other electronic devices in close proximity to the fish finder. Power up each device individually to determine if any are causing the problem.
Step 4
Shift the boat engine to neutral and gradually increase the RPMs to check whether or not the noise source is from the engine. Listen for noise during high RPMs, as this may indicate a problem with the alternator, spark plugs or tachometer wiring. Install an alternator filter, replace spark plugs with resistor plugs and reroute device wires away from engine wires.

Display Problems

Step 1
Check the positioning of the transducer if the device is not detecting fish, even if you can visually spot fish. Readjust the transducer, if necessary, so it is angled straight down.
Step 2
Reposition the transducer so it is at least 15 inches from the propeller. Move the transducer to an outer location if it is set inside a thick hull, as this may disrupt detection.
Step 3
Test the battery voltage. Low voltage can affect device signal transmission. Check the battery voltage to ensure the level does not exceed 20 volts, as this may trigger the device over-voltage protection feature.
Step 4
Inspect the transducer positioning if the bottom display is not visible or is fading while moving at high speed, which can distort the device's ability to interpret information.

Article Written By Mike Biscoe

Mike Biscoe has been writing since 2009. Focusing on travel, sports and entertainment topics, he has credits in various online publications including LIVESTRONG.COM and Trails. He often writes articles covering uncommon travel destinations from firsthand experience. Biscoe holds a Certificate of Completion in acting from the Pacific Conservatory of the Performing Arts.

Never Miss a Single Post

All our latest outdoor content delivered to your inbox once a week.

FREE UPDATES

Subscribe

We promise to keep your email address safe and secure.