Question: I have an annoying problem with my boat that seems to be getting worse. Every time I start my engine the electronics blink off and my GPS chartplotter has to go through its start-up sequence all over again. This is especially annoying when I’m out fishing, as we are often shutting the engine down for a drift and then have to restart to go and reset our position. Every time we do this my electronic equipment has to go through this reset. What do I do to stop this annoying problem?
Answer: There are several possibilities here. The simplest is that the battery you are using when this occurs is undercharged and when you attempt to start your engine the system voltage is dropping below your chartplotter’s minimum voltage requirements. Once the engine starts the alternator on the engine begins running and system voltage gets back to normal. So, as with any electrical problem of this type, always confirm the integrity of the power source before you start chasing ghosts all over your boat. You may need to get your battery(s) charged up with a shore-power charger, or run your engines more to let the alternator on the engine get the job done. You may need a new battery. Have you had it tested? Are the electrical connections on the battery clean and tight?
If you know that the battery and all its connections are good, and this is a new and worsening problem as you describe it, then you may need to simply start using the boat more to allow the alternator on the engine to do its thing. Beyond all of this, I’m a big fan of electronics-package UPS (Uninterruptible Power Supply) devices like the Newmar unit in the photo here. The one shown is for a 24-volt system, but they are also available in a 12-volt version. I’ve used these quite successfully to solve this sort of problem on more complex systems. The unit will take care of any voltage sags or spikes associated with engine-starting.