The steps below will walk you through diagnosing if you have an issue with your power, what that issue is and where it is located. If you find an issue with your power, you will need to resolve it for proper operation of your trolling motor.
Verifying Appropriate BatteriesYour batteries need to be capable of providing proper power to your motor. If the batteries are insufficient, you can have issues with using the motor including the motor only working for a short time, the motor working erratically, or the motor not working at all. Click this link for additional information on verifying you have appropriate batteries.
Lithium Batteries and Continuous Discharge Amperage
When using lithium batteries, you want to ensure the battery(s) provide(s) enough continuous discharge amperage to run the motor at its max amp draw. The chart below shows the max amp draw by motor thrust. If the motor is not getting enough amperage, it will have issues including working for a short time and then shutting off, being able to turn on the motor but not turn on the prop, steering issues, issues with i-Pilot and i-Pilot Link such as Spot Lock not working or being erratic. If you are having any issues with your motor and you are using Lithium batteries, verify you have enough continuous amperage available for the motor to pull its max amp draw.
Load TestingAs a battery discharges the voltage of the battery decreases. While batteries can typically be recharged from very low voltages you should consult your battery manufacturer regarding what voltage level the battery experiences damage that will limit its capacity in the future. Motor performance is highly dependent on consistent voltage, the battery system (battery and wires) should not experience more than 5% drop. To verify the battery system is good you can monitor the voltage as close to the motor as possible, when the motor is running on high, in the water, the voltage must not drop more than 5% (0.6 V on a 12 Volt system, 1.2 V on a 24 Volt system, 1.8 V on a 36 Volt system). If this is not practical the batteries can be individually tested using a load tester, then verify the wires are the correct gauge as identified on the Minn Kota wiring chart, and all the connections are clean (free of corrosion) and mechanically tight.
Verifying PowerYou can check your power by using a voltmeter to test the voltage coming off of your battery(s) and then comparing it to the voltage at the Quick Disconnect or Plug and Receptacle if you are using one and then again at the motor. The voltage at the Quick Disconnect/Plug and Receptacle and at the motor should match the voltage from the battery(s). If it does not, you are dropping power between the battery(s) and Quick Disconnect/Plug and Receptacle or Quick Disconnect/Plug and Receptacle and the motor or if you are not using a Quick Disconnect/Plug and Receptacle, between the battery(s) and the motor.
ConnectionsIf you are having issues with your motor and the batteries are charged, have been load tested (FLA, AGM or Gel) and are testing good, you will want to check the connections between the trolling motor and battery(s). The connections should be clean and tight. If there is any corrosion, buildup, or anything contaminating the terminals or connectors, they should be cleaned and then reconnect the terminals or connectors.
Quick Disconnects and Plug and ReceptaclesIf you are using a Quick Disconnect or Plug and Receptacle, check the connections coming from the motor into the quick disconnect or the plug to verify the connections are secure and the polarity is correct. Also verify the connections are clean with no buildup and no damage to connectors. Damage, corrosion, buildup, and loose connections can cause issues with power transfer. Next check the connections coming from the battery(s) to the quick disconnect or receptacle. Again you want a clean and tight connection with no buildup and no damage to prevent power transfer.
Circuit BreakerThe circuit breaker should be appropriate to the trolling motor. The chart below will show what circuit breaker is needed by motor. Verify the circuit has not been tripped and is in good condition. Also verify the circuit breaker connections are clean and tight and there is no buildup on the terminals.
Boat WiringThe rigging should be of a suitable gauge and in good condition. The chart below will show you what gauge the rigging lines need to be based on motor and distance from the battery lead lines to the battery. If you have wear on the lines or there is a break in the lines, you will have issues with power reaching the motor and could have a fire onboard. The chart below will assist in determining what gauge wire you need for the motor and the distance between the battery leads coming off of the motor and the batteries.
Visually inspect your rigging lines looking for any wear marks, kinks, or cuts. If you see any, replace the rigging lines. You can test for breaks in the lines by testing each line for continuity with a continuity tester. Another method, although not as reliable, is to feel the lines while they are in use, any warm spots indicate an issue.