In 2023 fishing is nothing without Fish finders. They help you see fish and map the water below. But what if midway, your fish finder doesn’t work? Don’t worry. We have compiled this guide with simple fish finder troubleshooting steps. These will help fix power related issues and more.

The next time when you are asking yourself “Why is my fish finder not working?” This guide is your go to solution. Let’s start with the Common problems and reasons

Common Problems and Reasons for Malfunction

Problem Reason Solution
Power Issue Insufficient power supply may lead to incorrect device functioning. Ensure your device is fully charged or properly plugged in.
Transducer Problems Damaged, dirty, or improper installation of the transducer can cause issues. Check the transducer for damage, clean it, and ensure proper installation.
Software Issues Outdated software or bugs can impact fish finder performance. Update the fish finder’s software to the latest version.
Interference from Electronic Devices Other gadgets on the boat can disrupt the fish finder’s signal. Keep electronic devices away from the fish finder to prevent interference.

Understanding these common issues can help you troubleshoot your fish finder and get it working. Now let’s delve deep into the topic

Imaging and Interference Issues

Imaging issues can mess up your fishing day. 

Problems Symptoms: Well, you could see fuzzy images, or worse, no image at all on your fish finder’s screen. 

Reason: These problems might come from your device’s settings or a problem with the transducer.

Other electronic devices on your boat could disturb the fish finder’s signal. This could result in erratic readings or a screen full of clutter and noise. Here are some of the ways to resolve the same 

Software Updates and Restoring Defaults

The software in your fish finder is its brain. It’s the system that helps it work and sense data. Regular updates can fix bugs and add new features to help it work better. To check for updates, 

  • First, visit the manufacturer’s website
  • Find the latest software versions
  • Download the one for your fish finder 
  • Follow the steps to install it.

Note: Remember to back up your waypoints and other settings before updating. This will save you from losing important data if something goes wrong.

Restoring Factory Defaults

Restoring Factory Default fish finders

If your fish finder is acting up and you can’t find the reason, restoring factory defaults can help. This step will erase all your settings and return the fish finder to its original state.

Restoring defaults is simple.

  • Go to the settings menu on your device 
  • Select the option to restore factory defaults.
  • This will erase your personal settings and data

Note: Make sure you have a backup before proceeding. Even after using the trouble shooting tips, if the problem persists, then get on call with an expert.

Troubleshooting Power and Connection Issues

troubleshooting power and connection issues in fish finders

Power and connection problems can cause a range of issues with your fish finder. Here’s a closer look at some of these issues and how you can fix them.

Fish Finder Won’t Turn On

If your fish finder won’t turn on, follow these steps

  • Check the power source
  • Make sure the battery is charged
  • Give your battery a full charge and try again.

If it still doesn’t work then it’s time to check the other factors

Bad Cables

Bad cables can also prevent your fish finder from working. Check for any visible damage to the cables. If you find any, replace the cables and see if the problem is solved.

Bad Wiring

Bad wiring is another common problem. This can lead to erratic readings or a complete shutdown. Get a professional to inspect the wiring. If there’s a problem, have them fix it.

Damaged Fish Finder

A physically damaged fish finder won’t work properly. If your device is damaged, it might need repair or replacement.

Corroded Battery Terminals

Corroded battery terminals can disrupt power supply. You can clean them using a brush and a solution of baking soda and water. But be careful not to damage the terminals.

Power Cycle Issues

Power cycling your fish finder is a good step to fix issues. This means you turn off the device, then turn it on again. This can reset the system and often solve minor issues.

Correct Wire Gauge, Type, and Connections

Correct Wire Gauge, Type, and Connections

Using the right wire gauge is crucial for your fish finder’s performance. The wrong gauge can lead to power issues. Check the manual for the correct gauge and type of wire to use.

Maintaining Good Clean Power

To work well, your fish finder needs clean power. This means a steady flow of electricity from the battery. Any power spikes or drops can cause problems.

Direct to Battery

Connecting your fish finder directly to the battery can help maintain clean power. This setup can reduce the chance of power drops or spikes.

Importance of Using a Correct Wire Gauge

A correct wire gauge is key for clean power. A wire that’s too thin can cause a power drop. On the other hand, a wire that’s too thick can lead to power spikes.

Soldering and Heat Shrinking Connections

Good connections are also important for clean power. You can achieve this by soldering and heat shrinking the connections. This will help ensure a steady flow of electricity.

The Role of Battery Health

Lastly, the health of your battery plays a big role in maintaining clean power. A weak or old battery can cause power issues. It’s a good idea to check the health of your battery regularly. 

Transducer Problems and Troubleshooting

The transducer is a key part of your fish finder. If it has issues, your fish finder might not work properly.

Sonar Image Interference

Sonar image interference can make it hard to read the fish finder screen. It can be caused by other devices on your boat or even by the boat’s engine. To solve this, try to keep your fish finder away from other devices.

Damaged or Badly Mounted Transducers

A damaged or badly mounted transducer can also cause issues. Regularly inspect your transducer for any visible damage. If it’s damaged, replace it.

If the transducer is not mounted properly, it might not pick up signals well. Make sure it’s securely mounted at the right angle.

Transducer Picking up Interference

Sometimes, your transducer might pick up interference from other devices. This could cause erratic readings. To solve this, check the wiring of your transducer. Make sure it’s not close to the wires of other devices.

Verify Transducer Install and Level

  • Lastly, it’s important to properly install and level your transducer.
  • The transducer should be parallel to the ground.
  • It should also be deep enough in the water to pick up signals properly.

Depth Sounders and Fish Finders: Specific Troubleshooting

Is the sounder operating within its expected capabilities (range)

Even the best fish finders and depth sounders can have issues. Here’s how to tackle some of the most common problems.

Problem: Malfunctioning Display

A malfunctioning display can make it hard to read the screen. This could be caused by a software bug. Try updating the software or resetting the device.

Problem: Power, No Display

If the device powers up but there’s no display, it could be a connection issue. Check the cables and connections to make sure they’re secure and intact.

Problem: Display Freezes

A frozen display is often due to software issues. Try restarting the device or updating the software.

Problem: No Bottom Readings

If you’re not getting bottom readings, the transducer might be the culprit. Check if it’s mounted properly and isn’t damaged.

Problem: Incorrect Depth Readings

Incorrect depth readings can be caused by a faulty transducer. Make sure the transducer is installed correctly and isn’t picking up interference.

Problem: Erratic Depth or Bottom Readings

Erratic readings often come from interference. Check the wiring of your device to make sure it’s not close to other wires.

Common Tips For Troubleshooting  

Check Connections

Faulty connections can cause your fish finder to malfunction.

  1. To inspect them, start by checking all the cables and wires.
  2. Look for any visible damage like cuts or fraying.
  3. If you find any damaged cables, replace them.
  4. If the cables look fine, check the connection points.
  5. Make sure they are clean and firmly connected.
  6. Loose or dirty connections can disrupt the flow of power and data.

Divide and Conquer Approach

The divide and conquer approach is a smart way to troubleshoot issues. The idea is to break down the system into smaller parts. You then check each part one by one.

For instance, if your fish finder isn’t working, start by checking the power supply. If that’s fine, move on to the cables. If the cables are fine, check the connections.

This method can help you identify the problem area quickly. Once you find the issue, you can focus on fixing it.

Depth Sounders and Fish Finders - Specific Troubleshooting forums

Fish Finder Repair and Maintenance: FAQs

Let’s answer some common questions about fish finder repair and maintenance.

Will a Fish Finder Work Out of Water?

A fish finder needs water to work. It uses sound waves to locate fish. In air, these sound waves don’t travel well. So, a fish finder won’t work out of water.

Are Fish Finders Waterproof?

Most fish finders are waterproof. They’re made to work in wet conditions. But not all parts might be waterproof. Always check the manual for details.

How Can You Prevent Fish Finder Faults?

You can prevent faults by taking care of your fish finder. Keep it clean and dry when not in use. Regularly check for software updates. Inspect the cables and connections often. By doing these, you can keep your fish finder in top shape.


Fixing fish finder issues can seem hard. But with the right steps, it can be simple. Here’s a recap of key points. Check power and connections if your fish finder doesn’t work. Use the right wire gauge. Keep the power clean. Check connections often. Use the divide and conquer method to find issues.

Transducer problems can cause many issues. Check for interference and damage. Install and level the transducer properly. For specific issues, check the software, connections, and transducer. 

Anthoni Ja
Latest posts by Anthoni Ja (see all)