Rolling Lines on the Display of a Garmin® Marine Monitor

Rolling lines on the display of the GMM™ (Garmin Marine Monitor) could indicate one of a few different issues. To resolve the issues of rolling lines on the display, try the following troubleshooting steps:

• Ensure the appropriate power cable (010-11425-08) is being used. This cable has a ticker gauge wire and a larger fuse than the power cable for the GPSMAP® 8500 Black Box. If the wrong power cable is used, and there is low voltage on the boat, the rolling lines issue could appear.
• Ensure the ground wire of the GPSMAP 8500 Black Box's power cable and the GMM's power cable are securely connected to the power supply's ground.
• If the above steps did not correct the issue, a different DVI (Digital Visual Interface) cable should be used. Cheap DVI cables have been found to cause this issue. Garmin recommends a DVI-D cable and we offer it in 6 feet, 15 feet, or 35 feet variations.