If your unit is experiencing power-related issues—such as touchscreen malfunctions, failure to power on or off, unexpected shutdowns, freezing, locking up, or loss of connectivity and other functions—we recommend using our Power Troubleshooting Tool. This tool can help identify and resolve common electrical problems. For further insight, you may also explore additional resources below covering voltage requirements, wire gauge recommendations, and battery specifications to ensure optimal performance and reliability.
Check Your Hardware and Connections
Check the Connectors & Pins
Check the pins of all connectors, to make sure they have not been bent, broken off or pushed back into the connector plug. If any connector pins have been bent, you may try to straighten them with needle nose pliers. If any pins are broken, replace the entire accessory.
Note: There is a risk that while straightening a bent connector pin, it can break.
HELIX and Legacy Models: Make sure the power cable has not been connected upside down. The notch on the plug (shown below) should point upwards for units with connections on the back. The notch should point towards the back of the unit for units with connectors on the bottom.
Check the Cables
Check all accessories and cables for nicks, cuts, or physical damage. Try to repair any nicks in the cable with electrical tape. If any cables have had the internal wires cut or separated, the entire accessory or cable should be replaced.
Try wiggling the cable leading into the connector of the power cord to show any intermittent connection. If the power cable is intermittent, replace it. On some fish finders, an intermittent power connection may cause the microprocessor to cease correct operation. This may make it impossible to turn the depth sounder off. If this is the case, return it to the Service Department.
Check for any Cards in the Unit
If there are any SD or Micro SD cards in the unit (LakeMaster, Navionics, etc.), try removing the card(s) and power on again. This could indicate an issue with the card causing the unit to freeze during the boot process, or prevent the unit from powering on altogether.
Temporary Issue: In some cases we have found that a Navionics card inserted in the left or bottom slot of a SOLIX running between software version 4.130 and 4.210, is preventing the unit from powering on. Removing the card or moving it to the other card slot will resolve the issue. If you are experiencing this, please watch for a future update that will correct this.
Check for Proper Grounding
Ensure the negative wires for your Humminbird products are not spliced into other negative wires. They need to be individually ran to a grounding terminal with the proper gauge wire for the device.
Products with drain wires, such as MEGA 360 and MEGA Live, must have the drain wire grounded.
Run the power direct to battery
By running direct to your cranking battery (or 12 volt accessory battery), with the proper gauge wire and proper sized inline fuse. This could identify a bad connection to the fuse panel.
Fuse sizes, power draw and the recommended wire gauge can be found here.
Test for Bad Connections
To determine if there could be any crimps, nicks, cuts or poor splices in your existing battery to panel run. If the unit works correctly, directly tied to the battery, we recommend that you look at your existing panel/buss, fuse and/or panel to battery wiring.
If the wire gauge is too small for amperage or power draw, this can also create an issue. For a 15-20' run of cable, we recommend 12-14 gauge, tinned copper stranded wire. Pay close attention to the gauge recommended for your unit as seen in our article on the subject or the unit's installation guide.
Check the Unit
If possible, test the unit on another boat with the same model number and accessories installed. If your unit functions properly on the other boat, you know the problem is in the installation, accessories or cables.
Check for Proper Voltage and Battery Health
To ensure your depth sounder or fish finder operates correctly:
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Measure Voltage at the Source
Check the voltage at the battery terminals or fuse panel where the unit is connected. This confirms that the device is receiving proper power. -
Refer to the Operating Voltage Range
Consult your unit’s Operations Manual for the recommended voltage range. -
Test Under Load Conditions
Measure voltage while all onboard electrical equipment is running, including the main engine and trolling motor at various speeds. This helps identify:- Over-voltage
- Under-voltage
- Electrical interference
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Diagnose Power Issues
If voltage readings fall outside the recommended range, it may indicate:- An inadequate charging system
- Wiring issues
- Battery degradation
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Seek Professional Inspection
Have your boat’s electrical system inspected by qualified marine technicians to prevent damage and ensure reliable performance.
Testing Batteries and Connection Points
Battery condition is critical and can greatly impact the performance of all marine products and their features. Below you will see the different ways of checking the condition of batteries.
JUMP TO: Wet Cell Batteries | Lithium Batteries | Testing Batteries with a Volt Meter or Multimeter
Testing Cables with a Volt Meter or Multimeter
Test both ends of the power cable with a Voltmeter or Multimeter to ensure there is 12 volts measured at both ends (terminal and plug). If there is a severe drop off from the terminal end to the plug end, the power cable is likely defective.
See the images of our different plug types below.
| PC 11/PC 10 (HELIX & PMAX) | PC 12 (SOLIX & ONIX) | PC 13 (APEX, XPLORE & MEGA Live) |
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| SAE Power Cables | MEGA 360 PC |
Wet Cell Batteries
12V Wet Cell Battery Voltage vs. State of Charge
| State of Charge (%) | Voltage (V) | Notes |
|---|---|---|
| 100% | 12.60 – 12.80 | Fully charged |
| 90% | 12.50 – 12.60 | Healthy range |
| 80% | 12.42 – 12.50 | Healthy range |
| 70% | 12.32 – 12.42 | Healthy range |
| 60% | 12.20 – 12.32 | Healthy range |
| 50% | 12.06 – 12.20 | Midpoint |
| 40% | 11.90 – 12.06 | Approaching low |
| 30% | 11.75 – 11.90 | Minimum recommended |
| 20% | 11.58 – 11.75 | Risk of damage |
| 10% | 11.31 – 11.58 | Risk of damage |
| 0% | 10.50 – 11.31 | Fully discharged |
Discharge Guidelines
- Recommended minimum charge level: 30% SoC (≈11.75V)
- Avoid frequent discharges below 30% to prevent sulfation and shortened battery life.
- Discharging below 10.5V can cause irreversible damage.
- Deep discharges (≥80% DoD) reduce cycle life by up to 58% in flooded lead-acid batteries.
Lithium Batteries
12V Lithium Battery Voltage vs. State of Charge
| State of Charge (%) | Voltage (V) | Notes |
|---|---|---|
| 100% | 13.6 – 13.8 | Fully charged |
| 90% | 13.4 | Healthy range |
| 80% | 13.2 | Healthy range |
| 70% | 13.1 | Healthy range |
| 60% | 13.0 | Healthy range |
| 50% | 12.9 | Midpoint |
| 40% | 12.8 | Safe zone |
| 30% | 12.6 | Safe zone |
| 20% | 12.4 | Minimum recommended |
| 10% | 12.0 | Risk of damage |
| 0% | ≤11.5 | Fully discharged |
12V LiFePO₄ Battery Voltage vs. State of Charge
| State of Charge (%) | Voltage (V) | Notes |
|---|---|---|
| 100% | 13.6 – 14.6 | Fully charged |
| 90% | 13.4 | Ideal upper limit |
| 80% | 13.3 | Healthy range |
| 70% | 13.2 | Healthy range |
| 60% | 13.1 | Healthy range |
| 50% | 13.0 | Midpoint |
| 40% | 12.9 | Safe zone |
| 30% | 12.8 | Safe zone |
| 20% | 12.6 | Minimum recommended |
| 10% | 12.0 | Risk of degradation |
| 0% | <11.5 | Fully discharged |
Discharge Guidelines for Lithium Batteries
- Recommended operating range: 20% to 90% SoC for LiFePO₄
- Avoid discharging below 10% SoC to prevent lithium plating and cell imbalance
-
Cycle life impact:
- 100% DoD: ~600 cycles (LiFePO₄)
- 80% DoD: ~900 cycles
- 40% DoD: ~3000 cycles
- 10% DoD: ~15,000 cycles
- Use a Battery Management System (BMS) to protect against over-discharge
For additional information on batteries and charge states please see the following links:
Testing Batteries with a Volt Meter or Multimeter
Testing a battery with a Volt Meter or Multimeter gives a quick indication of the current voltage of the battery. Note: When testing, it is important to remove all cables and make sure the battery terminals are free of corrosion and/or dirt.
- Icons on Volt Meters and Multimeters can vary though the most common is a V with a wavy Line
above the V for AC and a V with a Solid Line and Dashed Line
above the V for DC.
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Note: We recommended to follow the instructions and settings supplied by the Volt Meter or Multimeter manufacturer.
Testing Batteries with a Load Tester
Load testing a battery with a battery load tester applies a calibrated load and displays how the battery responds. The load is applied for about 10 seconds and the batteries should be at a 75% charge, a battery below this should be charged before load testing. Note: When load testing, it is important to remove all cables and make sure the battery terminals are free of corrosion and/or dirt.
Handheld Load Tester
Note: Follow instructions and settings supplied by hand held load tester manufacturer.
Computerized Load Tester and Readout
If you take your batteries to a Battery Dealer or Auto Parts Store to have them tested with their computerized system, it will create a Test Report for you.
If you are still having problems after trying all of the suggestions on the Common Check guide, watch this video for additional tips. If you still have issues, please contact our Help Center.
