Lost GPS and plotter detail



I have a NavNet 1723 C and a black box that I think is an 1824cBB NT. The serial number is 4324-7163 The black box and hub were installed in 2010. The units are not redundant. I'm not sure of the "how" but the result was that I used the CMap card in the black box for my plotter which displays on a Dell Monitor. Data such as depth and GPS data were able to be displayed on the Plotter display. Radar could only display on the 1723 C monitor.

On a recent trip I lost the radar. The display showed rings but no sweep of the radar. While attempting to get it to work, I apparently did something to cause the GPS info to stop going to the plotter screen and the data suddenly showed up on the 1723C. Now neither the plotter nor radar work. There are no loose wires or other obvious problems. There are no technicians in Ketchikan and I am at a loss.

Can you please help?
I've PM'd you our tech support info.

By the way...Murray Pacific Supply of Alaska at 907-225-3135 is an authorized Furuno USA dealer in Ketchikan.
I'll check with them but they are strictly retail and have no service dept.