Lowrance Hook 7 Problems And How To Fix Them – Troubleshooting Guide


Lowrance has been a leader in marine electronics since it invented the first consumer sonar device in 1957. Their Hook 7 fish finder/GPS combo is among their most popular products, appreciated by professional and amateur anglers alike. While generally a reliable device, some users have encountered a few issues.

This article will delve into some common problems associated with the Lowrance Hook 7, along with their solutions, enabling you to troubleshoot and optimize your device for an unparalleled fishing experience.

Problem 1: Inaccurate Depth Reading


One of the most reported issues is inaccurate depth reading, with some users reporting inconsistent or erratic readings. These types of situations can be dangerous for your outboard motor since you could enter shallow waters and hit the bottom with your propeller.


Firstly, you may want to verify that the transducer is installed correctly. Incorrect placement may cause inaccurate readings. Follow the Lowrance manual for proper installation and ensure that nothing obstructs the transducer.

Next, you could try resetting the device to factory settings. Follow these steps:

  1. Press the ‘PAGES’ button.
  2. Scroll down to ‘Settings’ and select ‘System.’
  3. Under ‘System,’ select ‘Reset Options.’
  4. Select ‘Reset All Settings’ and confirm.

If the problem persists, it could be a software issue, and updating your device to the latest version might help.

Lastly, if none of these solutions work, you may need to contact Lowrance Support for assistance or consider replacing your transducer.

Problem 2: GPS Not Working


Another common issue is the GPS not working or failing to acquire a satellite signal.


Firstly, check to see if your device is updated to the latest software version. An outdated software might cause connectivity issues.

Next, ensure that the GPS antenna is unobstructed. Buildings, trees, and even your own body can block GPS signals. Make sure you’re in an open area for the best reception.

If you’re still having issues, you can try a soft reset:

  1. Hold down the ‘+’ and ‘-‘ zoom buttons, then press and release the ‘PWR’ button while still holding the zoom buttons.
  2. Continue to hold the zoom buttons until the unit boots up completely.

Should the problem persist, a hard reset may be required. Note that this will erase all stored data, so be sure to back up your waypoints, routes, and tracks before proceeding. To perform a hard reset:

  1. Turn off the device.
  2. Press and hold the ‘PAGES’ button.
  3. Turn the device back on while holding the ‘PAGES’ button until the USA map appears.

Problem 3: Device Not Powering Up

Sometimes, Hook 7 doesn’t power up, causing distress to users.


Check the power connections. Ensure that the power cord is connected correctly and that there is no damage to the wires.

Verify the power source. The device needs a 12-volt DC power source. Ensure that the voltage is within the recommended range and that the battery isn’t depleted.

If these checks do not resolve the issue, it may be a hardware problem that requires professional assistance.

Problem 4: Screen Freezing

Users have reported instances where the screen freezes while they’re using the device.


This could be due to a software glitch. Firstly, try a soft reset (instructions provided under Problem 2). If the issue persists, perform a hard reset.

Additionally, check if your device’s software is up to date. If not, update it to the latest version. Regularly updating your device can prevent many problems, including screen freezing.

Problem 5: Inaccurate Temperature Reading

Inaccurate Temperature Reading

Some users report that the temperature reading on their Hook 7 is inaccurate.


First, ensure the transducer is in direct contact with the water. Inspect the transducer for any damage, and replace it if necessary.

Check if there are any software updates available, as they often include patches for these types of issues.

Lastly, a factory reset may correct this issue, but remember to back up all your data before proceeding.

Problem 6: Interference on the Display

At times, you may notice clutter or interference on the Hook 7’s display, which could disrupt your viewing experience.


Electrical interference from other devices installed on your boat might cause this issue. Try turning off other devices to see if the interference clears. If so, you may need to re-arrange your electronic devices or possibly shield your fish finder and its wiring.

Another possible reason for clutter could be the device settings. Try adjusting the sensitivity and the noise rejection settings in your device. Lowering the sensitivity and increasing noise rejection can often help clear up a cluttered display.

Problem 7: Lost Waypoints or Data

Another frustrating issue that users often encounter is lost waypoints or data.


First and foremost, make sure you are regularly backing up your data. You can do this via an SD card or Lowrance’s PC application.

If you’ve lost data, try performing a soft reset (instructions under Problem 2). This might retrieve lost data. However, if you’ve performed a hard reset, recovery might be impossible unless you have a backup.

Problem 8: Difficulty in Reading the Display in Sunlight

Difficulty in Reading the Display in Sunlight

Users have occasionally reported difficulty reading the display in direct sunlight.


The Lowrance Hook 7 comes with a brightness adjustment feature. To adjust it:

  1. Press the ‘POWER’ button.
  2. Scroll to ‘Brightness.’
  3. Adjust it to a level that suits your needs.

You can also try adjusting the angle of the device or using a sun cover to reduce glare.

Problem 9: Unit Turns Off Unexpectedly

Unit Turns Off Unexpectedly

Some users have experienced instances where their Hook 7 powers off without any prompt.


This problem could be power related. Check your power connections and source. Make sure the power cord is not damaged and that your power source delivers the correct voltage.

Also, ensure the device isn’t overheating. An overheated unit might shut down to protect the internal components. Keep your device in a well-ventilated area and away from direct sunlight.

If the problem persists, it might be a hardware or software issue, and contacting Lowrance Support would be advisable.

Closing Thoughts

While the Lowrance Hook 7 is a reliable tool that assists anglers in making the most out of their fishing trips, it’s not devoid of potential issues. The solutions provided in this guide aim to resolve the common problems you might face while using this device.

However, if none of these solutions work, don’t hesitate to contact Lowrance Customer Support for professional assistance. Regular maintenance, timely software updates, and a thorough understanding of your device’s functionalities can help prevent many of these issues and ensure a seamless fishing experience.