Check under "sonar" at installation. Make sure the correct transducer is chosen. If the correct transducer is chosen check the connections. If the connections are good check the transducer for a pinging noise or feel. Which one of these is not correct or not there? That is the problem. If all of these check out possible the unit. Can you check the transducer on a different locator? Can you check this locator with a different transducer, installed correctly of course?