I purchased a used Lowrance unit with LGC 3000 Antenna all worked fine when I purchased it. When I hooked it all up I get a message "GPS NOT Responding". I all the connectors are configured as they were. My question is there a test procedure usin an Ohm meter etc. to see if the antenna is bad or I have other problems. Just dont want to buy a new one and it not solve my problem. Thanks for any suggestions.
