The LGC3000, and prior models, were susceptible to damage from static electricity and other slight electrical variations. This is according to a conversation I had with Lowrance tech. support when I had to replace a fried 3000 for a 4000 (I did get a slightly lower price for the new one). The cause of the static charge? Removing/Installing my Aurora cover (felt lined). So, I could see how changing a battery, possibly with power to the NMEA 2000 network on, might do it.
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