I have a 797 C2 SI unit that is 5 years old. Suddenly it started acting up today. When powered on 90% of the screen from the center outward is washed out in a white color, creating a halo effect from the normal color (deep aqua blue) on the outer edges of the screen. Occasionally when we were at anchor or drifting the unit would power on normally, then after we stated moving it would shut itself off. Sometimes it will allow me to immediately power it back on, but it's a crap shot as to whether or not the screen will display normally or with the halo effect. Eventually the unit would not allow me to power it back on. So, I spent an hour fooling with it before I decided to remove it from the pedestal and remount it. It did power back on, but the halo was still there.
Batteries are not a problem as 2 brand new batteries were installed on the same day this problem started occurring. I have not been able to assess the connectivity of the power and ground wire connections yet.
Immediate and all help is appreciated as I have a trip planned this week and I will need the chartplotter to navigate. I called Hummminbird today just to check the time they open Monday morning, so I could get technical support. Just my luck!!! They are closed for the next two (2) business days for employee training. smh!