Furuno Model 1750 Radar not powering up

[shadowf1]

My Furuno 1750 will power up and start the warm up count down normally.
it counts down from 85 seconds to about 64 seconds and then powers off like someone pulled the plug on her.
I checked and rechecked the power cable and ground and found no problem. Has anyone else had this problem? If so how did you resolve it?

Thanks.