Was a constant never ending problem on lowrances I owned over about 6yrs never had one of ten plus units last longer than about 6 months It happened with both built in antena and external antena units "GPS module not responding" I had two units and one was always in the mail, they would simply send back a recconditioned unit. When they changed to a new model they wanted me to pay to upgrade so I bought a Garmin Think when they switched to the new style units it finally did solve the problem (poorly sealed unit h2O damage, moisture)Send it back to lowrance if you registered it and they will pro rate a new model. BRP owners lowrance makes your digital gauges Capt Matt