Fixing technical issues isn’t a skill everyone has. However, with patience and logic, troubleshooting Marine electronics faults is a process anyone can learn.
Many things can go wrong with boat electronics, and it’s not simple to figure out what the source of the problem is. Follow these few steps and you’ll be able to isolate the cause in no time.
Figure out what the actual issue is
On a simple level, a power outage on a device could be a fault of the device itself, the power cable, a fuse, a battery, a burnt out wire, or the power supply itself. So how do you go about figuring out what is the problem?
Think about what’s happened, what happened before during and after the problem occurred. What else was happening at the time?
Then see if you can duplicate the problem. If it’s an intermittent fault, this can be a frustrating process, so change one thing at a time. Is it related to something like a certain point in a cycle? Does it only happen when the surroundings or environmental conditions are doing something specific? You want to be able to duplicate the symptom consistently.
If the system is complex, isolate the item and test it as a standalone. If it tests fine, then add aspects of the system back in one at a time.
Some devices have particular scenarios or checklists to follow. Are there extra beeps? Is the screen flashing? Often there will be troubleshooting guide for that device. Google can be your friend here if you can’t find the manual. Check error logs, any self-diagnostics or other information that displays somehow on the unit.
On a boat especially, water damage and corrosion can be a common cause of problems. Keep an eye out for batteries with corrosion, green connections. Also, moving parts have wear and tear, which can cause physical breakages, other parts to overheat/ melt, cracks or clogged vents.
Techniques to try
Substitution: Trial and error by taking one thing out and replacing it with another to see if that fixes the problem. I.e., trying a new lightbulb, replacing a power cable.
Inspection: Look for visual sign of failure. This could be rust, corrosion, blocked vents and loose connections. Check the unit is correctly installed, especially if it’s a new unit or recently had a service. Check fuses.
Elimination: Taking parts of the system and testing them individually to see which bits fail at what point to isolate the cause.
Deduction: Logic. For instance, if you’ve just replaced a battery and now the unit is dead, logic tells us that it’s possible that terminals weren’t correctly reconnected.
Curiosity: If a part overheated, say, a power board, it is easy to replace the power board and say it’s fixed. But if they power supply to the unit is running at a high voltage, the power board is simply going to blow again. Be curious. Track the fault back and make sure the ‘cause’ is actually not a symptom.
Software: Make sure you’ve turned the unit off and back on again. Unplug the power cable from both ends and then reconnect- this solves a large percentage of problems as sometimes power cables can become loose by boat vibration or movement.
Is the unit running the latest software? Is everything else it’s communicating with operating the newest software? If one part of the system is older, is it still compatible with everything else? Remember when updating software, much sure the power supply is reliable for the entire duration, back the unit up first, and then once the update is running, don’t touch the unit until the system has completed the update and rebooted back to the usual display.
Check the power supply: Test for a short circuit by disconnecting the thing you are testing from the power source. Disconnect the load. Turn all switches to ‘on’ and place the multimeter (set to ohmmeter) across the negative and positive sides of the circuit. An ‘infinite’ reading means the circuit is good and the device bad, anything less than infinity indicates a problem in the wiring.
Check it’s not a grounding fault by switching off all equipment. Set the multimeter to the DC Volt setting. Leave the battery switch on. Disconnect the positive battery cable and take a voltage reading between the cable and the battery terminal. If it reads 12 volts, you have a leak. Turn the battery switch off.
Echosounder/ Fishfinder: Check the transducer connections and make sure the cable or paddlewheel isn’t damaged, fouled, or covered in growth. Ensure there are no through-hull fitting, zincs or strainers that are creating aerated water prior to reaching the transducer. Check the fluid levels in the transducer housing.
If images aren’t being displayed as normal, take the unit out of auto mode. Make sure there’s no frequency interference from other electronics. Sometimes, unshielded LED lights can cause problems at night.
GPS/ chartplotter: Check everything is connected to antenna and unit. Run in test mode to find out if satellites are being tracked. Ensure the chart card is inserted properly. Check the detail settings on the unit, adjust from least to most.
If you can’t find the problem, then contact Marine Services. They can find you the right people to fix what’s faulty, across the length and breadth of NZ.