Northstar 6000i radar overlay in suspend mode

[Fouraces59]

I have a Northstar 6000i with a radar interfaced in the plotter. I can get the plotter and radar to work individually and in the split screen mode. When I try to overlay the radar onto the chart the screen says SUSPENDED and nothing happens when I push the button.

Any Ideas?

 

[Northern bay]

Do you have a heading sensor installed?

 

[Fouraces59]

Not sure but believe so as I think it was working previously. Boat was my dad's and he had it installed and only used it a few times. Funny thing is today I noticed there was a box flashing NO GPS heading. Lat/Lon and TD's are locked in